It's been around a year (opens in new tab) since we last checked in on Door Kickers, and in that time KillHouse Games' top-down SWAT-like appears to have come on leaps and bounds. It's just reached beta status, words which here mean 'has added a levelling system for your troops, improved waypointing, a challenge system that rewards with XP, oh and this huge list (opens in new tab) of other stuff'. If you've bought into the game already you've likely received an email by now informing you of the update; for everyone else, the following trailer will clue you in on what you're missing.
Ahead of the full game this autumn—if that's what "final exams this fall" means at the end of the above video—this beta release boasts the aforementioned levelling system, new mission challenges that will help you accrue XP faster, an element of troop customisation, unlockable items and quite a few bug fixes, along with an improved modding system that will make it easier to change the game to your liking. (And that's only around half of the changes mentioned on the site (opens in new tab) .)
You can find Door Kickers in a variety of places, including Early Access on Steam. Considering the full release is only a few months out, it might be better to wait until then, when reviews will start to appear—but there's a lot here to get stuck into in the meantime, if you're determined to jump the gun.