Try running quarter-wave elevated radials, even 4ft above ground, and the difference is profound. Hard to do on a bare summit without extra poles but a world of difference with my Wolf River Coil vertical.
Thanks K3RW, next time I'll use 1/4 wave antenna, but elevated radials would have been quite a challenge in this location. I did try elevated radials in another situation but I think they have to be 1/4 wave high which is not always possible. I think that being this high (2800 feet) supersedes those factors, I was received very well in most locations. Thanks for the comment 73!
The elevated radials only need to be around a quarter-wave long, as they are supposed to be resonant. Try elevating them just 4 or 5 ft using a hiking pole.