Most of the above, not to do too much echoing. The standouts for me: The encounter guidelines worked, the fights were cinematic. Rituals. Since 5e, healing surges and utility powers are the things I miss most.
James Wyatt rules. That is why 4e’s cosmology was so good.Above all, the setting and cosmology. It's a thing of beauty, by far the best of any edition. I was very sad when 5E (which I mostly like) went back to the Great Wheel.
I quite like the pathfinder 2e multiclassing system, and it's something that could have been done in 4e had I thought about it, as something that they do in pf2e is have a campaign where everyone is a mystic and grant them bonus feats for wizard of druid class, or you could do a pirate campaign and grant all of your players the pirate archetype feat.
- Narrative Powers. Likely also something that annoys people, but things where the player gets to pass the stupid-ball to the enemies, mediated by the system... love that.
- MM3 monsters on an index card. Easy encounter design. Have a theme/the ability to invent decent riders/powers/etc, and you barely need to prep.
- Tactical fiddliness led to fun play/combos
- Best martials / most balanced(*)
- Healing surges: move some of the properties of healing to the target, not the caster.
- Attacker rolls everything
I didn't like the multi-classing system, but it works well enough (and appears to have inspired the multi-classing system in Pathfinder2). I much prefer the slower numerical ladder of 5e/bounded accuracy (cough*expertise feats*cough)
This.As an aside, I also knew young people (like, 20s; I was only 32 when it came out) who had never played D&D before but became huge fans and regular gamers thanks to 4e. This is while it was actively being disparaged online as an MMO and not-D&D. That means that WotC did something right with it.