It's been quite a while since I last played this, but other than a few bugs it seems like it's the same one I remember playing back in the day. It was pretty fun even with just the limited gear selections, but of course as you played it longer it got a bit repetitive and boring. Some people actually got past wave 250 in one go back then, but I bet it took way too long and was boring as fuck lol.
I agree with your points and I think the minigame has a lot of potential if we rework it properly, support.