I've seen missions go up as far as 700k, that's pretty good. If you consider that bounties against players start at 500k-2M, I'd say they're pretty nifty. Fighting against NPCs, even though it's though, is a no brainer. Even the toughest missions can be done from a fairly equipped fighter if you have enough patience to avoid fire while you take away the targets.
Problem is, there aren't really good missions (paying well) depending on the role you're playing. High profile missions are found on the Border Worlds. I'm under the impression that most missions in the Core Worlds won't even go as far as 200k.