When this thread turned up on my notifications, I was wondering why, so I went to the first post and, to my surprise, found that this was a thread I started! How strange.
Feats as "class-agnostic" class features is a fine idea in principle. Surely, if you had a (sub) class that said "you can use bows in melee combat without penalty" and it was archery-focused*, I don't think anyone would mind, but I can understand not liking a Feat that anyone can take to do the same- but at the same time, it feels like any archery-focused character would want such an ability, so if you limit it to one class, then people who don't play that class who want to use ranged weapons may feel like they're being short-changed. Or they ask if they can multiclass.
Which can end up muddying "(sub) class identity"** (if that's important to you). Now on the other hand, you could make every archery-themed (sub) class have their own unique abilities, but then you have everything you'd want to be a "master archer" spread out in multiple locations (I'm reminded of the Warlord thread, where people are like "look, you can be a Warlord with 3 levels of this, 3 levels of that, be a Halfling, take these Feats..."
Ahem. Anyways, the issue with Feats is mostly that the designers can't seem to agree on what they should do. Should they:
A) enhance existing abilities of a character (this Feat increases the benefits of Halfling Luck, or boosts Second Wind Healing!).***
B) let characters "opt-out" of system mechanics they find annoying or obnoxious. (This feat lets you grapple while wielding a greatsword!).
C) give characters completely new abilities (With this Feat, my Fighter can leap 30' into the air and Izuna Drop dragons!).
D) give mechanically-expressed flavor to a character (this Feat says I belong to a magical bloodline with deep ties to the setting!).
By having Feats be all four of these at once, and competing with (debatably) necessary ability score scaling, not to mention having fairly few Feats in the game (I think the grand total is 73 until the new PHB gives us a whopping 75. Woo!), I think it's safe to say that Feats are still pretty much a mess. The only real advantage is, we (mostly) no longer have Feats that make attempting basic combat maneuvers virtually unusable without them (nobody misses you, Improved Grapple!) and we don't have 3000 Feats to choose from. Still feels like a lot more can be done here.
*I believe the 1e Ranger had this feature.
**Speaking of Rangers, one of their core subclasses, is a grab-bag of abilities you can pick from that boost melee or ranged combat (some of which should either be core abilities, or perhaps Feats, because why are Rangers the ones with Whirlwind Attack?) which doesn't seem to have much identity at all.
***Examples given may or may not resemble real feats.