Here's a quick idea I had while working on some house rules for a new camaign where I'll likely have players who are completely new to RPGs.
In order to keep the amount of rules exceptions from specialized feats down, switch the levels where you get feats for character level with ability score increases, except for at first level. This only reduces the total number of feats at 20th level by one, but it does slow down their acquisition. The number of ability increases likewise goes up by one, which keeps PC power in the same ballpark.
Obviously this is just a really minor tweak and may not even have enough effect to be worthwhile, but again this is just something off the top of my head.
In order to keep the amount of rules exceptions from specialized feats down, switch the levels where you get feats for character level with ability score increases, except for at first level. This only reduces the total number of feats at 20th level by one, but it does slow down their acquisition. The number of ability increases likewise goes up by one, which keeps PC power in the same ballpark.
Obviously this is just a really minor tweak and may not even have enough effect to be worthwhile, but again this is just something off the top of my head.