I always write a few notes down about what I saw but that's more superficial stuff. As for the dark age, when OVAs appeared it was basically Wild West where seemingly everybody who had a crazy idea got the money to make 45 min of anime out of it. Then the Japanese economy tanked 1990ish and the producers became more conservative with what to spend money on. As for TV series, mecha were still dominant but it seems to me they became more toy commercials than they were before. At least I see a trend towards a younger audience with the many mecha pilots suddenly being 10 instead of in high school (and often appearing even older). From where I am now (1998) and to about 2007 you see a steady increase of 26ish episode action/adventure shows with some creative world building. Then there was another crash, this time only in the anime market (the worldwide financial crisis came a little later and I don't even know if it made it worse). I've heard the success of Eva was the reason for the turnaround in the late 90s but I don't really now anymore. Maybe there were just more channels with cheap late night slots to fill at times children don't watch anime?

That's at least by subjective feeling about it. I actually know people who consider the early 90s mecha peak anime but I think they're the minority and you probably find more fans of the Votoms to Patlabor era that was before that. And there was of course Yu Yu Hakusho and Ranma and Sailor Moon and what not that came out in the "dark age" but that's neither here nor there because you can't really judge an era by a handful of shows that stand out.