I thought Robotech held up fine -- better than I expected -- when I picked up the full collection a few years ago. Well, the Macross Saga parts; the other two parts (from two other anime) I had never seen before, and they didn't hold up well at all. But I persevered and got through them, just to see how well the adapters brought them into the Macross Saga parts. (Surprisingly not much needed to be done; just a few lines here and there. Elegant "angulation".)
Star Blazers, yeah, first season especially can be rough, although I cobbled together two feature length animated films out of season one for the nieces a couple of years ago. That artificially made things flow a bit better.
Random amusement: Star Blazers / SBY correctly (by accident) guessed that Pluto not only had (frozen) seas but enough atmosphere for (sort of) blue skies!

The second season runs better, partly because they based it on a single theatrical sequel film that they just added some plot filler to (and a happier ending). The TV movie and other animated theatrical films (through "Final Yamato") are... variable. Season three between the latter two theatricals, whuf. Doesn't help that the old English dubbing team was long gone and the replacements aren't as good (or as numerous so lots of the same voices in other parts.)
Modern Yamato film, trying to start another sequel series after the "Final Yamato" movie -- I've got, but I don't much like it. Looks great tho.
The live-action film from a few years ago? -- a few pacing problems, partly based on how they chose to end it, but otherwise impressive. The nods to modern Battlestar Galactica aesthetics were nice (including the diving warping battleship), considering Galactica (and even Star Wars) borrowed somewhat from the original series.
The modern season one reboot series looks great, but while I understand some of the plot changes (especially so that the series as a whole is more cohesive and less episodic and randomly bad science), I didn't like it as much as the old 1974 series for some reason I can't pin. I really should like it more. The plot differences after the first 1/3 aren't always paced well I guess? I should rewatch soon and see if I like it better.