You may need to alter the NPC stats in your db, as they now mean something. This is especially true about AC. If it's too high, players won't be able to touch them. If it is too low, then they would be too easy.
Quite frankly, combat is perfect now. AC, attack speed, dmg mitigation all line up with Live. What you are asking for is highly custom and not the purpose of this project. Maybe if you stopped whining for a minute and actually looked through the code yourself you'd realize how easy it is to change combat related code. In many cases, changing a single value drastically will alter your output. If you feel you cannot do this, then too bad and you have no right to complain.
Also, please use the custom forum for this. You'd get a much better reception there.
Chaos, as I said above the NPCs db entries now actually mean something. So, while the code is tuned towards Live, the db does not need to be. If combat is too difficult for small groups, then lower NPC AC or their STR. It will certainly make a difference now
You're correct, basic combat values should be made into rules, and I know KLS had that in mind. I'm sure they will be ported eventually.