I agree with @bobirobi20, it's difficult to make Julia's electrode with sonic boom threatening at 90's (& also more difficult to rebuild their teams with attacks/stats according to the levels scaled)
It would be fun to make it possible to basically "relive" the original battles. I know the trainers are stored somewhere accesible by the debug mode. It could be made to be more accessible (a "memory chamber" or a "time capsule" maybe?) to fight the original fights again.
It could be said that, again, Julia or Florinia wouldn't be at all challenging being that their levels are at most around their 10s, but, well, I think if all you want to do in Reborn is smashing a team of voltorbs at lvl 10 with your lvl 95 Hydreigon, this mod isn't for you. But it could be used to try other sets, to just relive the better battles of the game without the plot-related stuff (or with the TM's and everything else)...
Maybe a good thing that could be done to balance a bit the mod would be to take out the monetary reward to avoid farming for money, and maybe (or not) also the xp rewards?