All great comments. This is just what I was looking for.
I'll work on the controls feel first. My original concept was to make them very dependable, but needing a few tricks to get it to move exactly to where you want quickly (it makes sideways motion more dangerous - you can slide into some bullets that are off screen). However, considering these comments and that, as a Java 4k game the average play time will be less than 5 minutes, I'll make the controls easier.
Screen sliding - it seems to slide more when you hit the edge of the screen than when you move L/R within the screen. Feels like a bug.
The code even notes this as a bug - the "stickiness" of your ship on the side of the screen. Currently, the only way to see the motion is by noticing the background star field moving. I want to change this to show ship movement.
The gun action might need some tweaking, but I'm going to leave that for once I have some preliminary ideas down for enemy motion and bosses. The general concept is to make the player decide which weapon is better for a situation - the purple wavy beam which allows for maneuvering while still hitting the targets, but does less damage, or the direct ion gun blue straight beam which does lots of damage but puts you in more danger.
I currently don't have the code in place for scaling the objects on a per-instance basis (it's currently only in a per-template basis), but that should be easy to include, and will give some nice visual variations.