Any reasonably sized automobile can fit 5 people without problems. And that's comfortably. You can fit 4-5 people in the back of the car if you really try. So yea, I completely agree with you.
If I might chime in on this.
The one thing I can say is that it would be an improvement if money was more meaningful. I have been recording my income since last time (and will publish the next worksheet soon) but bottom line is once you max out the bar you will be earning more than you can spend and have mostly nothing to spend it on.
I mean, sure, you can collect outfits and such and try to get them all. But those things don't appeal to everyone and either way they will eventually run out. And there isn't really any long term reason to save money, nothing big to work toward or anything like that. If I weren't recording things I honestly could play the game without ever looking at the money counter at this point.
Now, I am not sure exactly how you could "fix" this in a way that works with the game and is actually fun. Or even if it needs fixing or if a "fix" would actively make things worse. But it is something to think about.
Well, legally speaking, thanks to seatbelt laws, 5 would be the limit, with 3 in the back. Squeezing anyone else in there would mean they have a good chance of being pulled over.
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As for the rest, IDK... I haven't really given this much thought, but just off the top of my head, maybe there could be...
Maybe activities around the hotel that could be purely optional, like helping Lin clean. This could give you +Obedience with the maids (maybe just the one on duty) and/or give you some extra money. You could show him in one of the girls' rooms, chosen at random, maybe playing with undergarments for people with that fetish, or the girl could be half dressed when you enter, with various reaction based on their exhibitionism stat? IDK
Maybe that one is just +to obedience, and he could help in various parts of the business, each with a different effect.
He could help in the bar for more money, with maybe some scene with Moon and/or Maria. More if you use the Strip Club idea, then Peni could also be involved.
He could work in the laundry, again for people with an underwear fetish.
He could serve drinks to people who are there to use the hot spring. Also earn him some tips and sexy renders of random guests.
He could help in the kitchen, for +Obedience to the maid on duty, and maybe some fun/sexy images of the maid, like Lin with some whip cream on her nose, and naked apron, milking Android while she is making a cake, etc.
Maybe do some gardening for ...IDK, +Lin, and a scene with either the fairies or one of the elves?
He could help Ellen at the front desk for +money and maybe a scene fucking her behind the counter while she is helping/talking to one of the girls... (alternately he could eat her out, so he is under the counter and can't be seen, so Ellen is trying to hide her reactions).