Powerful (generally considered OP by themselves)
- Great Weapon Master
- Sharpshooter
Useful (any character can benefit from)
- Alert
- Lucky
- Resilient
- Skilled
- Tough
Defining (specializes a character)
- Crossbow Expert
- Dual Wielder
- Elemental Adept
- Healer
- Heavy Armor Master
- Inspiring Leader
- Mobile
- Mounted Combatant
- Observant
- Polearm Master (often also placed in Powerful)
- Sentinel
- Shield Master
- Spell Sniper
- War Caster
Garbage (generally trap options)
- Athlete
- Actor
- Charger
- Defensive Duelist (could be defining, but weak)
- Dungeon Delver (could be defining, but weak)
- Durable
- Grappler (could be defining, but weak)
- Heavily Armored
- Keen Mind
- Lightly Armored
- Linguist
- Mage Slayer (could be defining, but weak)
- Magic Initiate
- Martial Adept
- Medium Armor Master
- Moderately Armored
- Ritual Caster
- Savage Attacker
- Skulker (could be defining, but weak)
- Tavern Brawler (could be defining, but weak)
- Weapon Master
This post highlights the exact problem with trying to rank certain feats in strength or usefulness is that many are subjective depending on player creativity or specific campaign. I mean no disrespect to this poster, but I completely disagree with more than half of his "garbage" list and have had numerous players take many of them often to great character defining effect. As an example it's downright surprising if any sort of deceptive character in our gaming circle
doesn't take Actor, and heavy armor master has saved the lives of quite a few tanks in our group (that little bit adds up over time). Skulker is also pretty much labeled a "must have" for any sneaky character with us, and we've had quite a few characters take both Tavern Brawler and Grappler (often both to great effect with combined or also with rage). Perhaps our games use far more grappling and social situations?
shrug
About the only feats I've deemed a bit too weak are weapon master, the armor proficiency feats, and
maybe Keen Mind, but that last one is only weak at our table because we have generous DMs who don't screw players over for not taking notes or care to not let players know what time it is in a game. And I've
still had no less than three PCs take it. I've seen just about every feat hit our tables on at least one character and while some or more situational, I'd hesitate to say any (again weapon master and the armor proficiency feats excluded) are garbage.
For the aforementioned weapon/armor feats, I just made a homebrew feat to replace them, giving the person a choice between two of the following:
1) Proficiency with all weapons
2) Proficiecy with all armors and shields
3) Any one fighting style
4) +1 to strength or dexterity.