@joey_zozo Aww thanks for checking out my website full of my silly projects and progress updates!! It's been a fun time haha.
The moon cow planet sounds like an interesting premise for a game world (and like it could be potentially attention-grabbing from the title alone if that's worked into it). And the concept of active play sessions vs. in-between menu browsing is actually something I've thought about while playing Pokemon Go of all things -- specifically the possibility of having a better distinction between play modes. For instance, if I already spent some time in the active "walking around in the world catching Pokemon" phase, but now I'm sitting on the subway and just want to browse my newly-caught Pokemon and send the duds to be ground up into candies or whatever -- but the game is still centered around my avatar walking around on a real-world map and nagging me with warnings about how I don't have a GPS signal, so I would tend to engage with it less. So I could see something like that but cross-platform helping to increase engagement in an RPG with a strong management component.
When it comes to Stardew Valley and the general gameplay loop, it is somewhat of a cycle as far as the seasons go, with a sort of progressive building up of resources -- so for instance you might work hard and do a bunch of mining the first year, and then use some of those resources to build better sprinklers to water your crops more efficiently the next year. From what I've seen the multi-player features don't seem to have a competitive aspect (and instead are geared more toward multiple people working together to build up the same farm) though I could see that as an interesting twist on it.
As far as monetization strategies go, I think I would have some misgivings about subscription model on mobile in particular... Maybe part of that is just my own perspective, where I need to be really into a game before I'll consider doing a monthly subscription (I think there's actually only one game I've ever done it for) and it seems like it would be hard to get to that point without some kind of free tier... Although I suppose some sort of "first month free, cancel anytime" type of setup might be an option to get around that.
I don't know though, competing in the mobile game market is really hard, and figuring out how to make money without a mess of gameplay-wrecking microtransactions is even harder (and certainly not something I can claim to have figured out with any level of success yet, haha.)
Anyway it's been really fun exchanging ideas on this stuff -- I'll be cheering you on and looking forward to seeing more updates on your project, and will definitely plan to start posting some gifs and stuff on here once my current project starts to take shape a little more :D