Interesting suggestions, I agree with most of what you've said. However, I feel that repeatable sex scenes are a waste of time and resources in a game that already has a scene gallery, unless said events had other purposes than just being sex scenes.
I'd be careful with implementing a grinding system too since a lot of people don't like grinding on a VN. I think the best way to approach this would be for every grindy aspect of the game to be entirely optional so people could just ignore it altogether.
Lastly, I think Catherine's quick climb through the mage's guild ranks is there to tell us players she has a unique affinity to magic, as was stated by Kyo at some point in the game.
Oh just to clarify, by "repeatable events" I didn't mean necessarily repeatable sex scenes, just quick things in general for Catherine to spend her days on outside of unique events (i.e "Catherine went to the gym and worked out today", or "Catherine harvested potion ingredients from wild plants").
I wouldn't even necessarily call them a "grinding system", they would be the least intrusive and time-consuming possible outside of any interesting scenes that could be added for fluff, just filler to pad out empty days assuming the game wants to preserve and expand the "daily management" aspect of it.
Catherine still has a stellar rise either way, but there's a difference between a rise that should take years only taking a few
months, and it only taking a few
weeks. Things like the day counter give the impression that the game's events are all happening non-stop, one after another everyday, but the way some events are written and common sense would dictate that some stuff should happen at least a few days or even weeks apart.
My suggestions were only for the scenario where the devs eventually choose to develop the "daily management" mechanics, if the devs decide instead to lead the game towards a more "pure VN" scenario, then it would make more sense to remove things like the day counter, and money and debt mechanics, so that the events can be left to happen over a vague time period.
Brothel is pointless since the aim of it was to help Catherine acquire gold to slowly pay off her debt, but we're waaay past that design and plot-wise ever since the switch over to a non-linear VN adventure instead of a sandbox. The only you could try to salvage that sub-chapter is to fit it in the initial cult investigations before the city invasion.
Plot-wise it could be adapted to be a way for Catherine to build her own information network and spy on certain people, in the same way Kyo did. Or just for fun, its not like a Catherine that chooses to work at the brothel doesn't enjoy a no-strings attached shag every once in a while if she has the time to spare.
