An issue I've found. When I start getting massively large amounts of bullets on the screen, they start disappearing. This wouldn't be TOO big of an issue, except that it seems to eat the angled ones quicker, and stops chains from self replicating. Then, once there are a lot of bullets being eaten at once, one of those bulky 25-30 hits ships flies across and eats all the rest, damping the chain down to zero.
A couple of issues I've had. One, you need to be able to delete buildings. Certain defense missions have gone on forever due to the fact that I have about 8 physics labs, 20 fighter bays, and 2 capital ship bays making super carriers. I just lost about half my base due to the flashback along the line of ships I had. 2nd. SLIGHTLY smarter AI. At least make them not funnel themselves into the hilariously massive explosion that is slowly creeping back down the line towards my base and the .1 second spawning fighters.
 "10 More Bullets"){kind=icon}
 "Obliterate Everything 2"){kind=icon}
 "Boxhead: The Nightmare"){kind=icon}