I do not think Aga can make a new class/race. Only PWI developers can do such a thing. So I would suggest getting in contact with them somehow.
I don't think they are asking for a new class. They are asking what you think a new class could be IF it was developed by PWI.I'd always thought something with guns/pistols would be next.
i think a gun slinger class would be awesome ... options like duel pistols or something ... plus have them stat'd so they are effective with APS ,DPS,DPH and high crit's... but have the disadvantage of PDef/HP