Perfection? Well, I also loved this game as a child, and I might be walking into a mine field here, but technically, since the color of the scrolled area is all yellow they should not have used bitmap mode. They could have done this much more efficiently using normal graphics mode, and the scrolling could have been pixel smooth and full screen.
In text mode, would it have had enough characters available though? 192 chars for the scrolling background (6x32), 16 for player+opponents (4 chars for ship, 4 for burner, 4 for enemy, 4 for enemy missile), 8 for stars, 52 for fonts, 10 for numbers, 1 for laser... That's 279 and I'm not counting the fuel gauge yet. Skip one font and you might just, just be able to make it.