It's not entirely clear, but considering Pareidolia wants this, and is unfeeling, it's likely Collector Sensei will be the embodiment of the worst parts of Sensei:
Sensei's morality and limitations will likely go out the window, then get torn to shreds like Sekai.
Pareidolia also implies he'll follow more in presumably Sekai's footsteps:
Overall: Collector Sensei will probably be more inclined to rape and abuse, and no girl will be safe.
Of course, that's just a theory. We won't actually know, until it happens, which seems implied to be after he's moved on from Maya, and probably submitted completely to Pareidolia.