The idea is alright, I'd even say it's good, but you can't, in fact, "endlessly escalate" the map becomes too small for comfort after some time, with AoE hitting your factories always. Upgrading your range becomes detrimental because of that. The idea is to "specialize your units", but you can't refund upgrades after you realize this. And in any case, even if you do separate your units by giving them different ranges, AoE will reach them after enough levels.

After a bit of time, you've also seen all mechanics the game has. There's a curve ball at one point - It's honestly a very good change of pace, and the game would benefit from similar things. Give us maps! A wall, a maze, an environment. Make each unit be able to do different things other than RPS. In the same vein, some could shoot through/over walls. Others could go through gaps, something a bit more interesting.

It also feels like there's very little incentive to actually... Destroy the enemy base. Sure, you'll be getting more resources because enemies get more factories (up to a point) and more spawn rate, them also being able to destroy your units will yield resources from those, but if you can keep a perfect balance between both sides you'll be raking in way more resources than if you actually try to win. The trouble you have to go through with them now demolishing you after a few wins is also pretty tedious, with your units not being able to do effectively anything for a while, and you're just stuck restarting until you kill enough of your own units to upgrade your way out of that hole. You could do a couple of things about the "destroying the enemy base" thing - Some kind of meta progression, a free (unique?) upgrade, or just making progression itself feel rewarding. But a level counter just isn't doing it right now.

I really, really want to like this game more. Please prove me wrong.