Now that feats are mandatory in the background I think that ship has sailed. But I also think the balance levels in this game are so rough anyway that you can account for feat balance and still not dip into overpowered in a no feats game.
Paladin isn't too good, with or without feats. But the monk is not good enough, with or without feats. They are too dependent on a single resource, and their damage is too low, and the nature of the drag on those limited resources forces them in a single path despite other things which look interesting on paper.
One solution is access to better weapons and the ability to apply their special damage to those weapons as well as their unarmed strike and weapon masteries. This allows them to do more damage, choose interesting things to do with weapon masteries, and not rely only on their special resource every round even without feats. With feats it allows them to specialize more in those weapons. But even at their peak with those changes they won't come close to the Paladins level of power. If somehow monk were using feats and Paladin were not, the Paladin would still outpace them easily, and not just in damage but in interesting options they could choose round to round. The gap is that large.