The 30a PWM can handle the 340w ok, so you could just add the extra 100 to that controller. That would be the easiest right off, then see how it goes for daily AH. If you still need more AH once you have tried it a little, then you might want to consider a more drastic solar upgrade anyway.
If you go MPPT on the 240, you must add the 100 separately to the battery via its own controller. The Vmp tracker works best with all same panels.
You could put the two 120s in series with the MPPT as 24-12 instead of 12-12 and get a bit more output in low-light or shoulder hours--no diff in high sun though.
You could yank one 120 off the roof and make that your portable and put the 100 on the roof instead (staying all PWM for mixed panels) That puts more of the total "aimed"
You could keep the money for the new MPPT, stay with the existing PWM, and spend that on a second suitcase 100. That would give you 440w.
Lots of choices!
