Mecha fans may want to look into Full Metal Panic (how many 'full metal' whatever to they have..?
). It's sort of combination robot and spy story, with teen romance and comedy. Some pretty big action at times, and then some slapsticky stuff too, but still fun. When all's said and done, it might actually be something that girls may like better because of the nature of the romance stuff.
The second season seems to lean more towards the comedy, and there are a few episodes especially towards the end tat have some of the funniest stuff you'll see. But the action doesn't get too allegorical/weird or such, so it's easy to follow.
I'm going to start including cover art/pics with recommendations...