I watched Gunbuster/Diebuster AFTER TTGL and oh boy did that make me LOVE those more than I probably would've. Gunbuster is my favorite anime of all time.
Gunbuster is so incredibly awesome...Too bad it was the beginning of the 'Gainax Ending' (Type 1) trend; Gainax blowing all their money on the earlier episodes (As well as beer and hookers) and ending with something that's largely still frames from the concept art and recycled clips.
Evangelion is still the only Gainax series that I'm aware of however, that has both a Type 1 *and* Type 2 Gainax Ending though. (The 'We ran out of money' and 'What the crap is going on here?' types)