Robotroll 3184 - Another attempt at recreating a classic

About a year ago I had a go at recreating the classic arcade game Robotron 2084 in GameMaker Studio 2, just for fun of course!
All started well, and I had a "brilliant idea" of having power ups, where you would pick up dollars as you progress in the game and use them to buy extras that floated around the screen. Suffice to say, after a few levels it got really boring and I shelved the idea, thinking that you might as well just fire up MAME and play the original, as it was way more fun!

Fast forward a year or so, and I thought I'd give it a another go, after playing both the original arcade game and my first pathetic attempt, a few things were realised:

1. Each wave must last no more than a minute, some maybe 30 seconds.
2. Fast and frenetic action is the key, if you include power ups, they must be readily available, no buying them with cash etc.
3. Originally supplied the player with shields that get depleted when you got hit, but this ended up being boring because if you had plenty of shields, you could just bash into things and there was hardly any jeopardy, so returned to "one false move" will kill you!
4. Toyed with the idea of a Defender-style smart bomb, but blowing everything up on the screen was a bit too easy! So included a Megaweapon which is basically a huge blast of 360 bullets in all directions! This has to charge up before it's used. 
5. Stick to the same principal of a claustrophobic blaster where the risk/reward factor is to rescue the humans, plus the added rush of seeing what your power-up will bring you.

The things added in shouldn't take away the fun of the original premise of Robotron. So, shoot the grunts and they'll occasionally drop a power up, grab it for instant blast power or points. More adversaries were also added, each one with their own behaviour and strategies.

After a rather nasty incident involving the "DEL" key I decided to use Github for proper versioning, so if you want access to the source code let me know. Although I must say the code really isn't complicated or doing anything fancy!

Anyway, here's Beta version 0.1 - Give it a go and see what you think, no keyboard control this time - it's gamepad only - left stick move, right stick fire. Plus right-trigger to fire the Megaweapon once it's sufficiently charged.