Can you go full corruption path? I mean is choosing corruption option most of the time result in me being in a bad spot later on?
No I don't think so. They become "your gang" and are corrupted to be submissive sex slaves to the mc. However, they seem willing and will let the mc do what he wants without complaint. Remember the basement scene with Nicole and Cassandra? I'm sure you can pull that off with Alexis and get a harem.
With the love route, the difference is that they act differently. They will drop hints, initiate sexual encounters with the mc, and generally act like girlfriends. I don't know how the love route affects the harem. It should not but it might.
AFAIK, the only thing that can get you into a bad spot are the interactions with Davide and the gang. If it's NTR on and you've got a good relationship with the gang but a negative one with the girls, that's where you're in the gang but get little to no sex. Negative relationship with both results in you being a voyeur with no chance of getting anything unless the relationships change.
Saddog is supposedly working on the update where the mc can eliminate the gang. Not sure how that's gonna affect anything. We need the dude to get an update out.