I'm a semi-total top who rarely ever bottoms unless the guy's god-hot and it's implicit there will be a flip-flop. I tend to go for dark hair and dark eyes but it's not a hard and fast rule.
My current dream bottoms are:
1. Gerard Butler: He would be got-up in his "300" gear, all sweaty and dirty, and I would be his Xerxes, ready to plunge my big ol' spear right up his tight gloryhole. Oh, he'd be Sparta, all right.
2. Eric Bana: For whatever reason, he reminds me of the first Darren on "Bewitched", only way more handsome; maybe, Darren and Samantha's son Adam all growed-up. I'd like to teach him a few magic tricks, at any rate.
3. Mathew McConnaghey: I'd fuck him hard and fierce...and make Lance Armstrong watch, to boot.
4. Bubba from "Mama's Family": I don't know what he looks like now but if I'd a time machine, Raytown in the year 1984 would be my first stop. He wears his jeans quite well.
I have a lot more but I don't wish to be a bottom hog and wear-out my welcome. However...
Bob, the personal trainer from "The Biggest Loser" looks like he'd be a wild screw and I just know it'd improve my cardiovascular health to pound his arse.