you know? I HATE INTS ESPECIALLY WIZZIES!
Okies, here's my experience... I tried a cleric/warlock, and he just kept dying over and over, so don't expect to solo with an INT unless you know how to survive...
Regarding your rogue, well yeah Foudre was right. and another lill info, you can grind on mobd 11 lvls higher than you with an average gear and a good xBow with xBow Extreme on, umm, oh yeah, without having cleric as a sub class... Cleric would help you survive the big hits/hp mobs... other wise, you're good with bard or any other sub classes...

I'd say stick to your rogue unless you want to party a lot, then go warrior or an INT...