There are a lot of comments here about which launchers are "close enough" to the Nova feature set, but very few people are talking about specific features and the alternatives that support them. I really just use two, and everything else is a cherry on top that I can do without if push comes to shove.
- Icons that open a folder if you swipe them, but launch the first app in the folder if you tap them. That way my apps all pull double-duty as both the one-tap app AND the list of alternatives I use less often.
- Google Now integration that swipes in from the left.
Action Launcher used to be my go-to, and it's still the best implementation of #1 because of the little indicators it adds to let you know if something is a "cover" (folder when you swipe) or "shutter" (widget when you swipe). Sadly it's gotten rather bloated over the years and spends more time force-closing from one glitch or another than it does actually running properly. Nova was my backup because it added "covers" a few years ago and I remembered enjoying the app about a decade ago. Now what?