Mahoromatic was pretty good, though it was based on a manga. Of course the second season had a horrible ending because the manga hasn't concluded and they had to make something up, but other than that it was a good series.

His and Her Circumstances was also well done. The lack of an ending in that series was due to the manga being incredibly long, but even with it basically just stopping, it's an excellent series.

Puchi Puri Yuushi, which is unlikely to ever be released in English, actually had a good ending and was entirely original. It was based on Gainax's own characters from the Princess Maker series of computer games.

These were all done after Eva. Gainax has lost massive amounts of talent over the years to other studios like Xebec, but they're not just sitting idle and releasing Eva crap. People still buy the Eva crap though and if it gets me another series like Puchi Puri Yuushi then I'm not going to complain.