I have a softspot for the eagles soft rock, but I have never really gone much beyond the overly rotated greatest hits plus hotel C. If any of you have a favorite disc please do tell...I did pick up a comp of all tracks from Linda Ronstats first 4 records for a rediculous price and have loved that much...
Re road tunes here is a widely varied selection as I find I need that kind of range from hard driving to slower on a long trip... they also tend to be a bit older as now a long trip in the car involves kids and they like the classics a lot of the time... :

Whichitah Lineman... Glen campbel
Phasors on Stun... FM
If I had a boat Lyle Lovett
Gimmie Shelter
california 1.... Decemberists
Goin Underground .. jam
carey... Joni M.
4 Winds ... Bright eyes
The watchmans Gone Gorden lightfoot.( If you dont know this song you should)
Do you know the way to san Jose... bacherach
This Chraming man

I dont think this works as a playlist, so these would be highlites in a longer playlist better organized...