Weapon Expertise is no longer a feat you can take. It's just too good of a feat for anyone to not take it. On the other hand, it is (eventually) needed. To replace it, everyone gets a +1 bonus to attack rolls at levels 5, 15, and 25.
Reasoning: attack rolls and defense values were intended to scale the same from level 1-30. At level 30, a PC will be at +15 +6 +4 = +25 from levels, magic items, and stat increases. This means that a level 30 PC hits as often as a level 25 PC should. There are ways to get +1-2 as you level to balance things, but no way to get +5. So to fix the balance, everyone just gets a flat untyped bonus at certain levels. Note that AC for magic armors already scales like this thanks to masterwork bonuses, but non-AC defenses don't have this fix built-in. There are long trains of defense boosting feats to make up for this. Since those aren't as vital, you still get to buy those feats if you want to bulk up your defenses.
