So, the first piece of advice I will ever give to anyone looking for mini wargames is... Case out your local area. Check the local gaming stores. If there's a Wargaming group for your region on Facebook, sign up and check in. There is pretty much no point whatsoever taking up a wargame if you don't have anyone to play against, and every part of the globe is different in terms of who plays what. Unless you're absolutely confident you can get a bunch of other people into whatever game you take up, your options should be strictly constrained to the games that at least a small group of other people in the area play, unless all you want is some pretty, nicely painted pieces of plastic to sit on a shelf somewhere. With that said...

Dropzone Commander, and its more recent, space-based spinoff Dropfleet Commander, are personal favourites of mine that I really miss having regular opponents to play with. DzC simulates a much larger battlefield than you'd get out of something like 40k, representing an area roughly the size of a large town or city district and forces that range from relatively small rapid-response task forces of half a dozen tanks and a company of infantry to large-scale battles between entire divisions. The game is interesting in its focus on planned maneuvers and, as the name might suggest, drop ships. Most DzC armies are somewhere between completely and near completely air-mobile, deployed via transports to developing hotzones. As such, determining where to drop your forces to engage the enemy is vital, since all but the fastest ground forces are far too slow to cover a significant portion of the battlefield over the course of the game. It's heavily objective-focused and offers a lot of strategic depth for a game that is, in general, fairly simple to learn. Dropfleet Commander is a space battle game set in the same universe, with fleets duking it out in orbit over contested planets and some focus on integrating with the ground-based game, though it obviously works fine on its own. It's kind of similar to Distopian Wars in play, though obviously in space and with heavily divergent focus and mechanics. The models are stunning and it's fairly new and not too expensive, so I'd give a hearty recommendation to check it out if you like fleet battles. The company who makes both, Hawk Wargames, is pretty small but definitely don't do GW nonsense. IIRC, there's a new edition of DzC somewhere on the horizon.

Otherwise, Infinity is a 28mm sci-fi skirmish wargame. It's great, I love it, and it's getting more and more popular pretty much everywhere in recent years (mostly as a result of people jumping ship from 40k) so the odds of finding a playerbase near you are pretty good. Plus the minis are very, very nice and you don't need more than 20-30 models to have a fully complete faction with numerous possible lists to play. Though obviously it might not be what you're looking for, considering you specifically mentioned hesitation about this style of game. Corvus Belli is pretty great, though. They've got a huge focus on keeping the game fresh and addressing any concerns from the player base, and I've got more faith in them than pretty much any other 'big' company. Plus all the rules are available for free and they have a really nice in-house army builder app that acts as a 'gold standard' for the game, keeping everything nice and consistent. Infinity really sets the bar for a company working really hard to make sure both the game and models are consistently the best they can be.

There's always WarmaHordes, as mentioned above, if you like that kind of thing. It's not my cup of tea, and I've heard some bad things about the current rules for Warmachine from some of the people in the area who are big into it, but I know PP is always working on that stuff so I expect it's a fairly safe bet that those issues will be ironed out before too long, if they haven't been already.