Well why not? why not have multiple business ventures and mini-game mechanics relating to them and getting and upgrading most of these businesses is the key to unlocking the later stages of the game? also add more branching in the different story lines so that you need to be at a certain point with different people before you can advance further on a specific person.
I personally feel that the sex with Debbie came to fast and too easy. There should have been more steps involving other people and quests before you finally got to have sex with her and alot more should have been required before we got Diane and her milk machine.
It's going to be necessary, after all, how else is he going to live a life of luxury, as a rich man in his sexy beach house, with all of the town's women hanging all over him? You have that pay for that lifestyle somehow. I suppose he could start his own sperm bank, as the sole donor... or replace Hugh Hefner, and start his own porn web site HubPorn, with variations for different people, like Porn Grub for the foodies, and Porn Stub for people into amputees, Porn Bub for gay porn, and Porn Bubba for Redneck Gay Porn, and Porn Dub for foreign porn, Porn Sub for S&M (even if subs are better in foreign films, this works better for the list), Porn Rub for massages? ...I am sure we can think of more. XD