i have a 4.5cc mempo if you want to work something out. don't have the exact numbers off hand, but something like 172 dex, 8ias, 76ar, 12%life. say cheapest 4.5cc/12life dex mempo on the GAH minus 10%? It'll up your DPS quite a bit, though you'll be taking an eHP hit
as for other upgrades...