1. I stay in pretty good shape, but I still find that getting my stuff to games is quite a workout. In my Oathbound game I typically bring: PhB, DMG, MM, MM2, PsiHB, MotP, D&dG, BoVD, KoKPG, OA, FRCS, Magic of Faerun, all 5 Splatbooks, Masters of Arms, and the 4 FFG Path of... class books.
This is ridiculous. And the stack has been growing over time because I use something from each and every one of those books.
I have *never* had to lug around so many books for any RPG before, even AD&D 2nd. I use a wheeled suitcase, for crying out loud.
Part of the problem is that I supply most of the books used in the campaign, but another part of the problem is that I want my players to have access to the kinds of character flexibility that they might enjoy with another system, and that means BOOKS.
I have a fighter/barbarian/exotic weapon master (2 books), who is developing a fighting school (Path of the Sword) based around moves from Masters of Arms.
I have a Bladesinger, but I use the Basiran Dancer base class from the KoKPG instead of that broken Prestige Class from Sword & Fist (Song of Celerity my foot).
I have a Bard with the extended music options from Path of Magic.
Going to a game session should not require a trip to the chiropractor.
2. New Book Syndrome. As many books as I carry to games, there are always new ones. Occasionally, the players want to try something from a book I haven't seen before. I try to be fair and give it a look, but that just slows the game down. And if I go and buy a new book that gets added to the game (Savage Species, for example), my suitcase gets heavier.
3. "Now where did I put..." this one really pisses me off. A character has something that we pulled out of a book because it was neat and when it comes up, we need to dig it out again. God help me if I happened to not bring the book. This is really a problem with spells because there are so darn many of them, even though I use a fairly limited set of available spells.
4. Character advancement takes forever. In a game where I can award a certain number of points and let the characters spend them, this is a quick and fairly painless process. I ask certain questions: (1) do you want to spend any EXP this time? (2) what skills and abilities did you develop this session? And so on. Leveling up in D&D is such a pain. There is a lot of erasing and scribbling and counting of points and adjustment of modifiers due to new feats and whatever. It reminds me of Rifts. Change one thing and erase half your character sheet.
5. I've noticed that my players approach character generation in terms of "what cool powers my character has." The first question I always ask a player is "who is your character?" D&D 3rd lends itself to the following: "I'm a gold-elf wizard-loremaster who specializes in transmutation spells." Which is not an answer to my question. D&D is great for new players - it has lists upon lists of powers and progressions and frameworks and it takes all the thought out of it. I've also noticed that players tend to take a long view of character advancement. "Hmm, in six levels, I can qualify for Force Wielder. Cool, so I'll take this feat, and these skills..." Don't really like this either. It's great for setting a character's long-term goals, but I hate it when it dictates chocies that are completely at odds with the way things have progressed.
So yeah, I think 3rd is rather GM-unfriendly. Especially considering that I have run games under Shadowrun, GURPS, White Wolf, and any number of other systems with equal if not more options for my players and could fit everything into a small backpack.
What really bothers me is that I was able to construct faithful conversions of all my characters with two half-sized BESM 2nd ed. books.
That being said, I recognize that there are ways I could deal with the problem.
1. I could restrict the options. I don't like this. I like options. I've played too much GURPS not to have options.
2. I could say "no" a lot more. This winds up being one of the first problems mentioned.
3. I could spend hours with a photocopier and compile a big binder o' rules. Frankly, I don't have that many quarters.