I've been hard at work on this game and am going to keep going until it is 'complete'.
A few additions: I've modified the whole system so that everything has hit points (including shots). That makes it much easier to create more and more powerful enemies and ramp up the difficulty. I've also made collecting the score multipliers essential because they also up your shots one hitpoint for every 10 collected. If you get far without collecting multipliers the enemies will eventually become very hard to destroy.
Also a multiplier drop is now guaranteed every 10 enemies destroyed (since they are now essential), and there is still a 5% chance of one being dropped randomly.
I improved the UI quite a bit and built an achievement system (15 achievments and counting).
I also added a proper title screen.
Also on my list is a 'shiny' mode for those that want it with lots of cool lighting and neon effects. This is totally hinging on me being able to figure that out lol.
Just messing around with adding a little visual flair to the game. Sorry for the mouse pointer! (yes, that is in the video). There is a little ship trailing effect, a slight tint to the whole screen to match the level color, colorful explosions to match the enemy colors and a few 'lighting' effects. They are easily turned of by flipping a variable (which will probably become a setting in the game)
There is an 'anti-camping' mechanism. If you stay on the same row for 8 second it sends out 'Goliath', a near indestructible ship to discourage you from staying on the same row for too long. Early in game dev before I implemented a level up system (collecting multipliers), on the busier levels you could shoot back and forth on one row without moving up and down and run up your score. That's harder now to do but i think I am still going to keep it.