Nice AAR! I haven't had time to play Baktria myself, sadly...

1. Use your elephants as much as you like. Looks like you earned them with those early battles in India. I haven't found elephants very effective in EB, but that was 0.8 with African elephants... If your EDB mod is causing Pahlava to build only elite units, you might consider using the console to give them a few eastern skirmishers (Gund-i-palta? the eastern Akontistai equivalent) or Peltastai just to make sure they have some units who can threaten elephants. If you get tired of elephants or they're not fun to play, the next king can be "fiscally responsible" and replace them with a half-stack of Pezhetairoi or hellenic cataphracts or something.

2. Sure, reload, why not? Some form of FD and/or console manipulation should keep them alive, if you pay attention.

3. I'm actually facing a very similar situation to yours in my Rome campaign - strong Pahlava fighting both an Indo-Baktria and the Yellow Death. Since the latter is so painful to deal with, I'm hoping to manipulate matters so the east will be interesting to play with once Rome gets there. The parts of my plan which would apply to your game would be: drain Ptolemy money via console, teleport their active armies to Cyprus, and add units to Pahlava in front-line cities and armies (or teleport armies they have from the east to the western border). Now that I've noticed there's a problem, I'll be training a diplomatic corps like QuintusSertorius did in his AARs, so I can FD provinces away from the Ptolemies and give them to Pahlava, Pontus, AS, or KH (maybe). That should be a lot quicker for Baktria to do than for Rome - you obviously have a diplomat near the Pahlava, just need one near Pontus and the Ptolemies now. And Hayasdan maybe, though they look fine in the 233 map.

With such a diplomat network, you could even force a "civil war" on the Ptolemies, similar to what Mediolanicus suggested. Asia Minor to Pontus, Mesopotamia, Syria, & Judea to a "new" AS, far southern Egypt to Saba. Then Baktria and Pahlava can fight over the remaining eastern scraps of the original AS without destroying the faction.