Thanks for the response, guys. I had a feeling that the transformer(?) was nothing to worry about. I think beachycove's hypothesis about bad solder joints, particularly bythe flyback and/or other video components, might be on the spot; that's the one area I didn't check thoroughly but - from the brief look I did take - believe could use some work. I do think that the capacitors are fine, for now - not that this is the most logical way to diagnose, but they definitely haven't started to fail on the logic board yet - and they seem to look fine on the analog board when viewed naturally; the light and angling of the camera may make objects appear worse than they actually are.

Meanwhile I'm about to finish treating the case parts with Retrobright (which so far has worked like a charm), so when that's done the Performa is getting reassembled, red video display or not. I'll try to snag a few photos of the bottom of the analog board before then, though.

Because of the sentimental value of this machine I actually would be interested in paying someone to spruce up the analog board (and hell, might as well re-cap the logic board, if they're all gonna fail eventually). As it stands, though, I'm leaving in about a week for ten months of volunteering and travel. Probably that wouldn't even leave enough time for one-way shipping. Maybe when I get back - I'm sure this place ain't going anywhere - it better not be! Soldering is definitely something I need to learn too, so maybe on some old cheap parts when I get back as Osgeld suggested.

Again, the input and suggestions are much appreciated.