It's a game. Probably just a cash-grab with half-baked content.
This game should be in a playtest phase, not a selling phase.
IT IS NOT READY FOR CONSUMERS.

Every time I play it I get annoyed at something new.

Seriously playing ONE MATCH shouldnt end with "I may as well lose, I can't win at this rate", since the ♥♥♥♥♥♥♥ spawns are SO ATROCIOUS that they always overwhelm you right at the 1 minute mark. I think the once or twice I've won is a ♥♥♥♥♥♥♥ fluke since this game is so damn ♥♥♥♥♥♥ with its damage and spawns.
Really, why does every helicopter have a thousand missiles that destroy multiple units each shot AND also just sit at the edge of the map, while still having 100% accuracy on my troops?

The amount of points you get at the end of the match is tied to how much you "spend" in the match (at least from what it looks like) and in those games you HAVE to spend EVERY SINGLE POINT or you WILL LOSE THE GAME. So good luck leveling your guns unless you slog through a billion losses, because you WONT be winning ever. Case in point I just spent 17 minutes nearly beating a mission to get 1k points - not enough to do LITERALLY ANYTHING WITH. There is no reason to have a grind in this repetitive, half-baked arcade game. If the missions were 15 minutes it would be worth it - plus you might actually WIN a few times, which its nearly impossible to do at the moment.

The lack of points you get with a successful run (I got literally 600 points on one win and HAD to be spamming the spawn buttons to not be overwhelmed - this was on map 2).
There needs to be a range of points you can achieve based on units killed and base health, rather than points gathered in the mission. This would guarantee replayability much further.
Then again - as I have said - this game seems like a cash-grab that wants to force players into the no-refund zone as fast as possible.

AND THEN upgrading is a terrible system, because to make your gun better you have to spend some sort of points, and you get so little of them per mission you can barely upgrade your guns more than once (IF THAT) after a mission, which does NOT help in the long run during a mission.
The RNG is also ♥♥♥♥♥♥♥ you over constantly. You HAVE to get good RNG on the upgrades or the enemy steamrolls you very quickly, and even then the upgrades are usually "Spawn 1 infantry", which isn't really helpful when SEVEN THOUSAND helicopters are shooting your troops already.

The next issue I have is that you have to be CONSTANTLY hitting seven different buttons to spawn troops, switch guns, spawn troops, switch guns. It becomes a mess of just hitting buttons over and over and then being on the wrong weapon that's reloading and then forgetting to spawn troops because you're shooting so you run out of troops then you lose constantly.

Sentinel Peak is really the ONLY good map, because you don't have to cover the entire map constantly for enemies. Its really the only fair map the game has in it.
Even the first map is literally impossible to beat despite me spamming the spawn buttons and "focusing armor" like the game says. Eventually the game just spawns so many enemies it doesn't matter how many troops or guns you have the enemy will just saunter into your base.

The RNG is also ♥♥♥♥♥♥♥ you over constantly. You HAVE to get good RNG on the upgrades or the enemy steamrolls you. And the RNG often sucks.

Also the tanks seem WAY too overpowered compared to everything else (Especially compared to your allied tissue-paper tanks) - an APC takes two rockets while I have to unload my ENTIRE PAYLOAD of weapons onto one tank, which then also forces you to not pay attention to other enemies for like a minute so your defenses get overwhelmed and you lose.

It'd be more fun if the win/lose rate was higher than 1 out of 10000 - or if the spawns/maps weren't so absolutely trash that it was POSSIBLE to win the maps, because at the moment some maps are nearly impossible to even start, and aren't worth playing.
The last three survival maps are also ♥♥♥♥ shows of spawners to the point where you instantly get overwhelmed - again, not a good look or entices you to want to play more.

This makes me assume (paired with the missions being 20 minutes long for no reason) that the devs are trying to force players into the "unrefundable" zone as fast as possible for no reason, or to force you to keep this game.

Right now I think its basically a cash-grab game, especially since they are advertising THREE more games on the title screen. I will not assume they are going to finish any of those games, considering they are going to be developing four games at once in the future.

Until the ♥♥♥♥♥♥♥♥ spawning and lack of power in the weapons you use is fixed, this game is not worth your time.

TL;DR
It's 'eh' at best, it's just definitely not balanced properly at all - The RNG, upgrades, spawning system for enemies and allies - So the game isn't fun for more than 10 minutes. The 2nd survival mission is the only one worth trying since its the only one you wont want to throw your computer across the room playing.

The Good:
Vampire Survivors meets the AC-130 gunship killstreak from COD. At time of writing the review, I'd treat it this is an expensive, full release, quality game. It tickles the lizard brain in all the right ways, I honestly think this makes for an awesome mouse trainer, if you're into that sort of stuff. The rotating camera means you're exercising all directions and choose the weapon for the skill you want to practice. Tune the persistent upgrades to tailor fine movement training. Each level is a different type of target room. Only thing it's missing in this regard is a laser weapon with no hitlag. Dumbbell Games, you're missing out on a demographic, get the word out! I appreciate the bodies getting flung and gibbed, because in real life, everything just gets turned to mist. Doesn't trigger the PTSD as much.

The Bad:
Some voicelines can get repetive
Not a fan of the friendly unit spawn mechanic
Not much music variety
Still missing some features for a proper mouse trainer.

General feedback:
Some upgrades shouldn't be shown together, such as don't have a 25% reload buff and a 50% reload speed buff for the same weapon be shown together. Only bug I've had was my napalm launcher bugged a couple times and exploded point blank and blocked some of the camera with fire. The friendly unit spawning needs tweaking, and the unit spawn level up bonuses are rarely worth it. Have the unit spawn level reward drops buff those units instead. I find myself spamming the buttons to keep enough dudes alive to pick of the couple of units that survive the barrage more than tactically spawning them when needed.

This game is ridiculously fun. It's a gunship defense game with roguelike elements, everything works as you'd think it would and it all feels pretty good.

For myself this is an easy buy at 10 bucks.