I currently play a warlock, and I think that while having the Eldritch Blasts being ranged touch isn't really that bad, it's horrible when your DM likes to throw enemies with a low Dex and lots of armor. My DM and I eventually had to come up with a class defense bonus that overlaps with armor to reduce the effectiveness of his eldritch blast, because he frequently told me "You didn't roll a nat one? Then you hit."
Of course, it might also have stemmed from the fact that his ranged attack is +10 at 6th level (18 dex, Weapon Focus, Point Blank Shot), so he has a better chance at hitting his targets than the warforged fighter does.
Swashbuckler (from AEG's Swashbuckling Adventures) I once played one of these for a 4th-level one-shot, and I was able to use a combination of feats that made my AC so high that the mooks that we were fighting could only hit me on a Nat 20. It's an amazing defensive class (at least when combined with Swashbuckling d20's feats), but it lacks in the damage department and doesn't have the hit points of a fighter.