About rearranging

Prerequisites

Before even thinking about rearranging, be sure to have read help skills, help stats and help rearrange.
It helps if you understand what they say too. :)

About bonuses

When you type 'skills', you will probably see a list with entries like: 

    covert..............   54  204 
    | stealth...........   81  214
    | | inside..........  100  226
    | | outside.........  125  240
The first column gives the name of the skill, like 'inside' (which stands for covert.stealth.inside, as you can see from the form of the skilltree). The second column gives the level in that skill, 100 in the case of co.st.inside. The third column shows your bonus, which is what this is all about.

Although for some things, like learning new commands or for your guildlevel, level is important, it doesn't actually reflect how good or bad you are at things. Your bonus determines your chances of succeeding for skillchecks. So, if someone notices you sneaking indoors, this is because your 226 bonus was not enough to win it from their perception bonus.

Your bonus is determined by your level in a skill, and the stats that are important for the skill. For example, covert.stealth.inside has 3/5 dex, 1/5 int and 1/5 str. So, your bonus in it is determined by function1(level co.st.in) * function2(D, D, D, I, S), where D is your stat in dexterity, I your intelligence and S your strength.

Therefore, if you want to be good at a given set of skills, and you find that the stats relevant for these skills practically always contain wisdom (you can find the stats relevant for each skill on this website, in the "Skill/Stat Relationship" section), you probably want to raise your wis a bit. Of course, this means you have to lower another stat: the sum of your stats has to stay 65 (or below, but that would just be silly ;).

But be warned! There is more to stats than just bonuses. Stats have have consequences on many things, and these things can be both a reason to consider rearranging in the first place, or a reason to refresh after rearranging if you didn't think about them properly. In the next section, I will go into these important and all too often overlooked details.

Some things to keep in mind

Rearranging is delicate business. It will open new possibilities and limit you in other ways. Before taking the step, be sure to keep all consequences in mind. Here's a list of everything I can think of.
If it's getting a bit much: relax. You have the time. Probably. Browse through the site, maybe make some notes. And once you think you have found a good rearrange, just come back to this page and check whether you are going to have problems with anything mentioned here.

burden

Your strength affects how much weight you can carry before you get burdened. If you get burdened (score burden gives a value of at least 50%), you lose a dex point, and lose more the more burdened you get. When carrying too much weight, you won't even be able to pick up new things. So basically, you don't want to be burdened.
However, there's more to burden than just being unburdened. If you want to use dodge as a defence, you will find it much more effective at low burden (below 10% if posible, but below 20% is often considered a must). So, even though fighting.defence.dodging doesn't have a strength component, you probably need the stat to be able to dodge effectively.

health

Your number of hitpoints is determined by your adventuring.health bonus, combined with your weight and the constitution stat on itself. Your health bonus, as you can check easily, is mostly dependent on your con stat (and your health level of course), with a small str modifier. Your weight is mostly determined by strength, with a small con factor (check the "hitpoint computer" for more detailed information).
Therefore, if you want a lot of hitpoints, you need more than a good adventuring.health bonus. With low strength and con, you will need a much higher level than someone else to reach the same number of hitpoints. For example, with 8 strength and con, you need about level 710 to get 3000 hitpoints. Without rearranging, you'll have that at level 375.

guildpoint (and hitpoint) regeneration

Every heartbeat you regenerate some hitpoints and guildpoints (and 3 xp and one social point). The amount of hitpoints and guildpoint regenerated depends on your stats.
While your hitpoint regen may be of some influence, most people use other healing methods like tea, small gods water or curing rituals, to regain hitpoints faster than just waiting. It is good to think about it and have a look at the section about it, but most probably it won't define how you play your character.
Guildpoint regen, however, is very important (once you get past newbie levels, and have some decent guildcommands). Having a regen of only 2 guildpoints per heartbeat can make a character close to unplayable. 4 gp/heartbeat (rather than the average of 3) is quite addictive, and gives a great edge in PK fights, I heard.
Your guildpoint regen is determined by the logarithmic average of your stats in your guilds' point skill. So, if you are a priest, your guildpoints regen is determined by the logarithmic average of the stats that make up faith.points, that is, W, W, I, I, C (W is your wisdom, I your int, C your con). Better information and a calculator are given in the section about "regeneration rates".

The usual lecture

The rearrange command allows you to change your stats, but only once: you lose the command after using it. Therefore, you should have a complete rearrange in mind before rearranging and believe you can stick it with it for the rest of your time playing this game. You can move some stats afterwards, but it is expensive and - what is infinitely worse - can only be done about once every 20 weeks.

A common catch with rearranging is that people do not think ahead enough. When my pacifist Pishite rearranged, I thought I would never get enough xp and rearranged such that, eventually, I would have 300 bonus in two important skills. When I reached that, 3 days of playtime later, I was stuck with a silly rearrange.

Basically, this can be prevented by two things: playing the character for some time (preferably with talker on the guildchannel), so you get to know the possibilities and problems of the character - this is still wise to do if you have had characters in other guilds, as my Pishite found out - and thinking before you rearrange.
If you think you will play this character for a long time, write down your goals, but remove the skills that won't need more that 300 bonus (unless there's a lot of them, and they all need comparable stats). If, at some point, you'll be ready advancing them, reaching that point is just xp. Thinking longterm, it's easy enough to reach those goals, even with a bad rearrange, and even if you do not numberchase overly much.
Don't take me too serious in this, though: it is still good to keep in mind the skills that matter to you in the short term. If you rearrange in a way that will make you a great wizard after a year of playing, but doesn't enable you to do much before that time, you probably won't make a year. An alternative is to choose a rearrange with a few stats different from your ideal long-term rearrange, and go to the retrophenologist (which I will say more about below) a few times to move statpoints. However, because you can move only one statpoint every 20 weeks or so, this will keep you for a long time on a rearrange that is neither your initial rearrange or your ideal rearrange, and therefore might well be completely sucky.

Alinearity

I understand that this section can be quite confusing, especially when you're rearranging for the first time. If your mind starts/is buzzing, just stop reading here and skip over to the next section. I added it because it can be useful information to know and keep in mind, especially when you know the global form of your rearrange but are unsure about the exact details.

You may have noticed the 'logarithmic' in the section about hitpoint and guildpoint regeneration. To determine regeneration rates, but also bonuses, the mud does not just use the weighted average of your stats. Instead, the product of the relevant stats is used in the calculation. This means that low stats will affect the 'average' slightly more than high stats.
For example, while the skill covert.points is determined by 2/5 dex, 2/5 int, 1/5 con, having 18 dex, 18 int will give you a slightly higher bonus than 19 dex, 17 int (although this difference is so small it takes very high levels to notice). You can try this yourself with the "Bonus Computer" on this site.

Another thing that is not entirely linear is the raw bonus formula. You may notice that the bonus for skills at low levels grows much faster than the bonus for skills at high levels, whatever your rearrange is. This is because a different formula is used for the levels 0-20, 20-40, 40-60 and 60+. However, after level 60, the bonus formula is linear: each level, your raw bonus will grow with the same amount (although rounding and your stats may make it seem a bit strange, sometimes increasing with one point, two points, or no points at all).

O dear, I screwed up.

Your rearrange isn't as good as you thought it would be. O dear.
There are a few options left:

Okay, I think this is everything I can say about it. Good luck!