Agreed that traits should have more of an impact on roleplaying and not just stats, but a simple solution might just be to make all traits at least somewhat valuable to all classes. For example, +1 con vs + 1 speed, +armor vs +elemental resist, +gold found vs +experience obtained, +initiative vs. +starting AP, etc. Of course, some people will always try and min-max and decide one of those stats is better for their character, but something like +1 SPD vs + 1 CON is a much harder choice than +20 backstab hit chance vs. literally anything if you're not a rogue. Most people will just be like "Oh well, Speed and Con are both good, so I'll just go with whatever I get" instead of "Well shit, I'm a rogue, I guess I HAVE to be heartless."
