I've never felt that 2E was particularly well balanced. Plus it is a very deadly system too. As for being easier to run, I don't think there a difference between running any of the D&D editions as a DM. It all boils down to the same amount of work, just with different rules. And just about any edition makes the rules so much more simple than 2E.
Settings can be ported to any edition. But best priests and fighters? With the huge amount of options, prestige classes and feats in 3.5, arguably the best versions of either class can be made in 3.5. And again, I personally feel that 2E is one of the least balanced editions. Especially in regards to deadlyness, and the difference in combat effectiveness of the classes as they advance in level.
If you want to do something non standard, wouldn't the edition with the most books for it be far better? Not only does 3.5 have a huge amount of books for it, but you can also use Pathfinder books, and other OGL books. There are infinitely more options. Also, Conan RPG 2nd edition uses the 3.5 system, and it is amazing!
I've always felt that high level campaigns are 2E's biggest weakness. It clearly wasn't designed for high level play.
