That's actually one of the things I like about D&D as opposed to most other RPGs (just RPGs in general, even CRPGs) is the level-up system. I hate to compare it to video games, but the level up process on RPGs for most consoles is so cheesy. You fight a few bad guys, level up, and suddenly you're twice as strong as you were a level back. I don't think you should get that powerful that quickly. With D&D, leveling up doesn't make your character jump in power that much. The HP may be a little overkill at some points, but basically when you level up, you get a few small bonuses that, after a while, really start to stack up. It shouldn't be instant uber-power when you level up. It should be a gradual process. That's my opinion, at least.
I agree with that totally, my gripe is how some games implement that. for example losing 12.5%-25% of your blood puts you in serious medical danger but a blood donation is normally about 8%-12% which your body can easily handle. anyway this is never going to change no matter how fit or strong you get, but you do get better at avoiding blows or deflecting it so it doesn't hurt as much when it hits, which I gather is part of the system of this new game which is awesome.
Update I've been really busy for tthe past couple weeks on my game. To this point I have the Character creation, character races and classes, skills, gifts, experience system, and the combat and damage system finished. For the record the game stands at 12 character races and my class system goes with three classes but 15 overall aspects of those three classes. First the character chooses one of the 3 classes but then chooses which one of the five aspects of the chosen class that they want to work with. I still have quite a way to go and the magic system is going to be tough. It's alot of work and it gets very engrossing for me so I tend to go silent for a bit. If you are still intersted I will keep up with the updates.