"He's not an asshole" is completely basic, bare minimum you'd expect from a person, so that it wouldn't outweigh the lack of other desirable traits is completely fine.
I'm reminded of
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, which I read once or twice a year when I'm feeling stymied.
That said, Nice Guy isn't
just nice. He's running a (largely) successful charity, and involved with a few small businesses. He's a surprisingly talented photographer. He's an avid reader. He's a great cook. He exercises, and takes care of his body. He has hobbies, and interests, which exist outside of his ability to throw money at things. It's these qualities that (more often than not) actually attract the love interests in the game.
Nicki's close with Guy, because of their shared interests. Ashe's optimal date outcome occurs when you show interest in her thoughts and opinions, valuing her outside her (admittedly great) tits and ass. Gabby cozies up when Guy shows an interest in her art, and recognizes which art school she's hoping to attend. Brittani does the same when she sees her goth photos, and Guy accepts her constructive criticism regarding her shoot. Carolina's best outcome, is when Guy demonstrates he could be a good dad to Maya. Mason and Guy bond over their shared love of bad sci-fi. I could go on, but you get it.
A lot of people tend to dismiss the relationships in the game as being only due to money. But, I see it more as these things being
facilitated by money -- including Guy's confidence. There's really nothing about most of these relationships, that would
require Guy's money, besides that said wealth put him in the right place, at the right time.
If Guy had nutted up and just told Nicki how he felt? Well, who's to say they wouldn't have gotten together? Or if he'd met Ashe while trying to rollerblade, and gotten a few tips from her, without looking at her tits? Or if he'd met Gabby at one of her art shows, and used his understanding of comics art to appreciate the stories she's telling in pictures? Or, or, or..
I may have just talked myself into doing some Wanton Weekends content around Guy meeting all the girls, sans wealth.. :'D
NeonGhosts, you better let us save Viola's mom!

Well
fiiiine, if I must.. Nah, we'll likely meet Viola's mom in Chapter 11, actually.
Is there a Harem path in this game or something like that?
Not what one would call a traditional harem, where all the girls love you and are cool sharing you. But, you can be involved with multiple girls at once, on various routes.
Can we see scenes with Brittani's mom in any future update?
She'll be there to supervise Brittani's audition.
.. for good or ill. >_>