The game isn't perfect, that's for sure. There could have been ways to make the open world less painful, but it also makes it feel more "narrow". For example, you could get quests only from guilds or other specific NPCs, meaning that you'd only have to check those for new quests, and/or use more the balloon to indicate the availability of new content. I don't like that approach, though, since you are just moving from marker to marker at that point. The best approach would have probably been to not use a chapter system, so that everything is available when you enter an area (barring quest chains, but those would usually give you guidance on where to go for the next part), so you don't have to search the same places every chapter, and/or open up the world a bit more gradually as well as making travel a bit more involved, so that you work your way up to the full open world. There are trade-offs no matter what, though.
While I do have some amount of interactivity between the factions you are a part of and some quests, that can quickly spiral out of control if you have characters interacting consistently. I would have had to cut the number of characters, most likely.
Sonya just likes to be the queen of her little reign, that's why she doesn't go far with manipulating a noblewoman. She just sees Erica as another one of her girls (even if Erica is definitely one of her favourites). The QoH has gambling, sexy bunnies, strippers and a VIP area (which is usually very expensive and exclusive, although you gain entrance in different ways), these are all activities which make a ton of money, and she also has all sorts of special deals for rich customers. Also, don't forget she can effectively bamboozle everyone that comes in with her powers, to an extent, while the brothel is just a "regular" brothel, at the end of the day.
Kira's panties are the top 1 unique item in the game. XD
Anyway, that's more or less my thought process behind the game as far as these elements go.