If you haven't already, check out the Live From Daryl's House with Darius Rucker (lead singer of Hootie & The Blowfish, also a successful country musician in his own right), their voices work really well together IMO.
https://youtu.be/9Zz1r7qEQck
They are top of my list of bands I really wish I'd got around to seeing live.
I'm not sure what they're doing these days, but I don't think I'd want to go and see them without Glenn Frey - would be missing far too big a piece of the jigsaw.