Basically, much of the Superman runs from the early to mid 90's were the best. Dan Jurgens, Karl Kessel (SP?), Roger Stern, Louise Simonson, etc, were some of the best runs I've ever read.
Jeph Loeb was either hit or miss. He was nothing spectacular, IMO, but you could check him out if you want to see for yourself.
John Bryne's early work on Superman is good, but thought balloons aren't for everyone (personally, I'll never understand what the big deal is about that).
The Kessel Hawk and Dove run was one of the best comics runs of all time IMO