They wanted cartoony for a reason - so it would print well.
And this is just my opinion, but...
If you want Jeff to listen to your suggestions, <i>explain</i> them.
I don't mind pointers, constructive crit is great, but if someone was just harping on me without explaining anything...I'd be put off and offended myself.
And personally, I've seen tons of photoshopped stuff. Maybe it's because I'm interested in drawing, but I prefer something hand-drawn (well) over just another photoshopped image anyday.