I have yet to hear a set of strings that doesn't sound good on a TBird. I've used LaBella Flats, TI Jazz Rounds, Rotosounds, Epiphone
, D'Addario slow- and regular wound, Elixier coated strings, DR Black Beauties and Lo Riders, GHS Bass Boomers, Warwick Black Label, Status Hex Core and Dean Markley. And a handful of others I've forgotten. They all sounded slightly different with the LaBella Flats and the TI Jazz Rounds obviously the most radical departure from a traditional roundwound sound, but still great in a different way.
I play with a pick and prefer - on a Bird - a medium bright, warm sound which is not yet clanky or piano-ringish.