Any fighter or bomber that were involved in the Polish campaign, invasion of the Low Countries and Scandinavia and during the Battle of France should be added to the EW ETO plane set.
For the most part, at least on the Allied side, most of the planes that were involved in the onset of the war in the PTO flew the same EW rides as they did in the ETO, so quite a bit of those Allied EW ETO planes could also be added to the EW PTO plane set, would just have to change the skins. Would be cool flying I-16s with Nationalist Chinese markings. I would also add all the Japanese fighters like the Ki-27 or the Ki-21 "Sally" or the G4M "Betty" bombers.
In addition, EW ground vehicles like the French Char B1 tanks, British Matilda, German Panzer I, II, and Panzer III Ausf.F and Ausf.G and the Czech made German tank Panzer 38(t) and Panzer 35(t).
ack-ack