If you need to drive both dynamic and planar cans, then you’re going to be limited to transformer-coupled tube amplifiers (or hybrids, but that’s a different discussion). OTL amplifiers tend to be current-limited and need higher impedance than most modern planar cans exhibit.
Off the top of my head …
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WA22 - not my personal favorite, but certainly competent as far as things of its ilk go. Don’t get too funky with tube choices.
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DecWare Taboo MKIV - the Taboo was built to drive the original LCD-2, and handles more modern planar cans even better. Very fast. Very detailed. Rich, sonorous, though colored (part of it’s charm for me). One of my favorite amps. Odd aesthetics (I like, but still a bit steam-punk). Relatively long lead-time. Separate L/R level controls can be a pain.
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ZMF Pendant - revised since I last heard it, but thoroughly competent and at home with both dynamic and demanding planars. Stock tube complement is less “tubey” than most; recommend that you either take Zach’s tube upgrade option or read the Pendant thread for alternatives.
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DNA Stratus - exceptional, though not the best match for really demanding planars. I like it best with dynamic cans. Good 2A3 tubes get spendy, though it sounds very good with basic tubes.
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Woo WA5-LE - for $4K you’re either going without the “parts upgrades” or buying used. Mine had the parts upgrade (makes it closer to $5,000). VERY tube dependent. @andris has the standard WA5-LE and some good input on tubes for it. I wound up putting tubes that cost more than the amplifier in mine while I had it.
The EC stuff is excellent, though discontinued, but I didn’t spend much time with planars with those amplifiers (the Studio excepted), so you’ll want to solicit other opinions on those.
Feliks will come up, but I’m not a big fan … not because I think they’re bad - it’s a value thing. I liked them better before prices jumped. Power is limited for current-hungry planars.
amps&sound have some interesting options. I like the overall designs and sound. Build is excellent. Support is first-rate. I’ve had noise-floor issues with them in the past, with higher-impedance outputs, however. This could be down to tubes, as the units I’ve heard had stock tubes and these amps generally use tubes I do not have lots of options on hand for (I tend to stick to “big SET” stuff). Talk to Justin if you have concerns before buying, he’s a great guy.
Nothing else comes to mind at this point, but I am sure others will point out options I missed.