I am going to make mine a cafe.
I am doing only one thing at a time when it comes to mods/service so I don't end up with a basket case (been there, done that). I got lucky with a tight strong bike, so my problems are minimal, and I ride it almost daily.
It has lots of low end grunt, and is extremely fun on tighter "slower" roads, but hitting 70+ winds the bike up....I am considering adding a tooth to my countershaft sprocket to get some more top end. Ideally, I would like to be in 4500 to 5000 RPM at freeway speeds, and not howling at 6000+ like it does right now.
My Clymer manual says 10-30 for the forks in one place, and ATF in another, anyway, I slapped in some fresh 10-40 (195cc) in the forks, and wow, what a difference! The old oil was totally shot when I got the bike, right leg had ATF, and left leg had old stinky dead ass motor oil.
She handles great, but with some clip-ons, I am willing to bet she really handles awesome, and the cafe conversion has me very excited. I am 200 pounds, and to bang 70+ I gotta lay on the tank, so the cafe conversion should suit the bike perfectly IMO. For cruising though, it is a really classic looking ride, and turns heads. Either way you go, it can't hurt, the 500-550 CB's are strong little girls.