I think you're right, in a way, on both accounts, that is in your first paragraph, you may be saying the potion is the vehicle for him to get laid in secret and 'not damage his Victorian image/reputation'. And in your second paragraph you're noting the film's, may I say, ridiculous theory about the good of separating the good man and the animal man -- which is not in the novel, and something I didn't like about the film.
You didn't mention what you thought the potion represented. In the short story (only about 170pgs), I think it's alluded to even more than in this or other films. I kind of think it's a bit obvious. I think it's alcohol. For many throughout history it's the potion that causes inhibition, and for some allows, or causes, people to lose contact with their higher brain function, empathy, morality, love and self control. Of course it's also a symbol for whatever else acts to do the same thing... a theory, a practice and societal system. But he does drink it, doesn't he?
Here's a quote from the film about the why he made the potion (which is not in the short story).
So, in the bold, is where it's ridiculous, that is, it doesn't really make any sense within itself. Liberate evil to fulfill itself so it troubles us no more? I'm guessing he means do it, the animal impulses, to get it out of your system? Yeah, like that ever worked.
Both the book and film do point to the same thing, in that, even so with the alcoholic, the more this activity is done, the more it entrenches itself into the person/brain/psyche/soul, not the other way around. It, 'evil', or unchecked selfishness, and insanity, emerges even without the potion, and can't be reversed even with the antidote, so to speak.
Of course I recommend reading the short story, as it's only 170 pages. Love to hear what you think.