I have a Symmar 210/370 convertible that I like. As a 210 it's a really sharp modern lens with smooth out-of-focus areas and a nice look for portraits on 4x5". I don't often use the 370 side, because I have a 360mm Tele-Arton for 4x5" and the 370mm configuration (rear cell only) requires more extension than my Tech V has to offer, so I need to use it on an extension lensboard if I want to use it that way, and I prefer to leave it set up on the flat lensboard, because it's cammed as a 210 with infinity stops set for the flat lensboard. The 370 isn't quite as sharp as a real 360mm lens, but stopped down it's still pretty good, and it could be practical if you have a camera with something like 20" of bellows, or if you're willing to deal with the extension lensboard.

I would think that if you wanted to put together a compact, lightweight setup for LF a good combo would be a Symmar convertible in the normal range for your format (150/265 or thereabouts for 4x5", 210/370 for 5x7", or 300/500 for 8x10), plus an Angulon (more compact, less costly) or Super-Angulon (sharper, bigger image circle, but much larger and more costly) at the wide end.

For 8x10", there's also the venerable Turner Reich Triple Convertible that Ansel used for a while (at f:64, all lenses start to look the same on 8x10"), usually something like 12-19-25", but there are a few different versions, it seems.