Ok, went through it, and it is quite hard, different difficulty-settings or game-modes(focus arcade vs. focus on strategy) are some options to consider.
Another thing to note is that you have one type of "alien," and even though i read a bit in this thread about multiple skills, i have a hard time imagining a game with only one type of opponent keeping players interested for long.
Most play testers find it very difficult to play despite adding detailed, in game hints. I need to know why my clues aren't being picked up.
First of all, let's distinguish between "in mission" hints and "out mission"(mainly the design-screen) hints.
"in mission" -short shouts (shoot this, catch that) are needed, the player is busy firing at opponents, not reading a book.
"out mission" - full explanation of what something does, here should also be explained the strategic aspect of the game,
when i started i assumed i had X lives, now there seems to be a resource-system that buys ships and other things ?
I saw a "scanner"-option the design screen, btw, and for a game like this it makes sense to having it available on default, like you proposed with the nuke.
Say the scanner needs ~40-50 seconds to make a complete scan, from then on the player can retreat and adapt his ship.(and get full info on what the aliens are currently carrying)
edit:i just finished the game, it's not that hard when using cloak so you can easily catch e-pods.
I didn't realy adapt to the aliens though, just used the best available options.
The automatic e-pod-catcher only works once, maybe make it unlimited use but have it consume 1 (earth) resource upon usage ?
Repairing-specials didn't seem to work, but maybe i pressed the wrong button ?(i ve gotten the hint to use space and the hint to use shift iirc, though i m sure usage of specials was tied to up ? anyway, players should probably get to adjust their button-settings before finishing the game)
And the shield-key seemed to give me a bug(or was it intentional?) there was a lot of space in the shield and it was hard to figure out how far off my ship was,
i kinda expected to just appear on the other side of the screen so maybe it was my fault, but a range-indicator(how far from the battle is the ship) would be desirable.