The people who dislike the branching paths are just being idiots, and I'll explain why.
As far as I can see there are only 3 branching points here. They all make sense for the plot, and offer the opportunity for further divides.
Branch 1: Fuck Mia's mom, or fuck Mia. This makes absolutely perfect sense, the scene building up to it was hot as fuck too. This is where I could see it going in the future.
Chose to fuck Mia's mom: She is a good little slave. However don't forget she is NOT above tying her daughter to a fucking bed, and you control her mom there for you will control her. This could be a 2nd branch off point where Mia wants to run away, and go live with her dad in his new place, they wind up fucking... you catch them, or the exact opposite. Mia's mom ties her to the bed for you 24/7. You can come in and use your rape slave until she is compliant.
Choose to not fuck Mia's mom, and fuck Mia by default: Her parents catch you having sex with her and then you gotta propose to her or something maybe with that diamond ring in the attic... Mia is your wife in this line, and your slave in the other. This could also branch where you don't want her as a fiance, and you spill the beans on Mia's mom being a lesbo slut slave... Could be interesting...
Branch 2: Sex ed with yoga mom or get a girlfriend for her son
Sex ed: Leads to all sorts of 3 some possibilities. Maybe your friend wants to fuck your mom with you too.
Branch 3: Get a girlfriend for yoga mom's son, or snatch that girl for yourself again lots of different opportunities here.
Give him orc girl: This means you fuck yoga mom, and maybe some voyeur on Eric with his girl... Maybe his girlfriend walks in on you fucking his mom... Maybe they get serious, and you fuck his girlfriend, and he get mad at you.
Keep orc girl for yourself: Well your buddy basically resorts to fucking his mom. Maybe you spy on them a bit. Also you get that nerdy orc chick for yourself... I can see her in a lot of different cosplay shit. There are lots of things here.
That being said... All of these branches, and a whole lot more could not happen in a very realistic manner if you just get to fuck them all in 1 line the same way... Just because you don't fuck a girl NOW does not mean she is cut off in future lines. Nothing is stopping you from fucking orc girl for instance.
Branching can be good, or it can be bad... It all depends on how it is written.