Yeah, they have the same last name and there's also the whole thing about Christmas gifts, and why Tiffany says she can't stand her family. Jessie is kind of sleazy, she is a porn star, or "adult movie actress". She's that really really chill person when it comes to sex. I think she's the only one who is openly okay with polyamorous relationships. More love to go around, I believe is her belief.
Lola is nice. I like her too, but as you said, not as much as others. She's got pretty cute outfits and hairstyles for sure.
Oh my gosh, Aiko is my favorite. She's just so pretty *~* and she's nice. Kinda depressed, but still a nice person, likes to have fun, perhaps enjoys gambling a bit too much
Beli is probably tied with Aiko though. For all the reasons you state. Something funny about her VA, she also voiced Android 18 in Dragon Ball Z. Quite a bit of difference there haha. And Silver, let the game consume you!