In fifth edition, feats are substantially more powerful than previously - each feat enables a new approach to playing with many situations. In Pathfinder, you would need a collection of 3-5 feats to make yourself an effective defender; in 5e you just need Sentinel. You might take a whole slew of feats in Pathfinder to be good with a bow; in 5e you need Sharpshooter.

But there's a problem - feats are more powerful, so they are rarer. They don't usually enter the field until level 12, since the first and second Ability Score Increase (ASI) are both dedicated to your primary attribute, which affects almost everything your character does - going without it costs a lot. Players do it anyway; making your character interesting to play is usually worth more than making it effective. I don't think players should have to make that choice! Even worse, there is one race that can get a feat at level 1 - Humans; as a result, munchkins never play any other race.

In my 5e games, I let players have both - every ASI comes with a feat attached to it, instead of having to choose between them. I also give all characters a free feat at level 1 (the Human variant gets two feats). It makes the games a bit overpowered in the midlevels, but it actually brings things back into balance at the high levels - the feats matter a lot more to the martial characters. It also means that more players are willing to take feats like Actor, which have really interesting applications, but little combat relevance. DMs always have to adjust the difficulty of encounters based on party composition anyway, so it doesn't cause any real problems.

You don't get the choice-induced paralysis in new players that you might remember from 3.5, because there aren't any really wrong choices - every feat will do something interesting, and there are some feats that are good choices for literally any character. Don't know what to take? You can't go wrong with Alertness or Mobility, and Resilience is probably a safe bet!

One mechanical issue does crop up though - because some feats give +1 to an ability score, we needed to make the additional rule that your stats are limited to 17 until character level 4 and 19 until character level 8. Just to keep the munchkins in check, of course.

Note: I consider myself a 'munchkin', and I don't consider the term insulting. I know some groups that do, but please don't take it that way - when I talk about munchkins, I mean 'optimizers', not 'rules-lawyers'.