Ross is actually not good for most boss fights, except for the ones where you're forced to use him. I hugely prefer either Cecil or Shauna. I actually think I prefer Cecil in most cases, but if you build up Shauna's HP a bit, she has better defense and hits nearly as hard if you can reliably do Murder on Demand. Cecil just has better and easier overall scrolls though.
The drug factory is pretty much a dead end, so don't worry about it. The hideout, on the other hand...well, if you explored the whole thing by following walls, you should have way, way earlier found someone blocking a door. He's no longer there, so you should have a way in.
Congratulations. You're nearly finished the game.
slight
spoilery
tip
There are galactic dusts at every single save point in the game. Most of them are hidden. It's possible to miss a few, since there are a couple of points where you can never come back (Ross's dream sequences in particular). So I hope you got those. If you didn't, then you're going to miss out on an area of the postgame. It's nothing utterly game-changing, but it's a good thing to have.
Check out my Manamon text walkthrough at the following link:
https://www.dropbox.com/s/z8ls3rc3f4mkb … n.txt?dl=1