@joey_zozo Interesting, I really like the idea of a single-player RPG where you can occasionally spin off multi-player quests, especially in the context of some kind of larger progression system or meta game. I'm actually curious if there are any existing games out there doing something similar or that you consider an inspiration? It seems pretty unique to me, though I may be out of the loop.
As far as my own game design philosophies... I've been focusing on mobile so far in my little #GameDev journey, and was motivated to try making my own game largely by disappointment in a lot of existing mobile games. Mostly due to the monetization tactics -- microtransactions, and "gameplay" that seems to be designed purely to try to manipulate you into spending potentially unlimited amounts of money on them. I envisioned "free to play" mobile games as functioning more like a free demo, where you could try it out and then optionally choose to pay some finite and knowable amount of money to get the full experience if you want... Which may be less profitable, but I felt like it would be a much less terrible experience for the player, and felt inspired to try making the kind of games I would enjoy playing myself.
Another thing I think about a lot for mobile is play session length... I think I read that the average play session is something like 7 minutes for mobile games, which seems pretty consistent with my experience -- there have been some good fun games I've played on mobile, but I would notice that if it takes a 15+ minute commitment in a single session or else lose progress, I would tend to not even start up playing them in the first place. (Though admittedly, this was probably more of an issue before all the quarantine lockdown stuff started, when I was mostly playing mobile games during my train commute and it was important to be able to pick it up and play a little bit on the fly.)
So taking all that into account, mechanics wise, I wanted to combine the short-term idle nature of typical mobile games (tapping on colorful things in puzzley and satisfying ways) with the longer term goals and progression systems of a more traditional RPG (so all that fun tappy gameplay wasn't pointless, it's a way of working / grinding toward something bigger). And even if the minimum play session length was intentionally kept super short, it would also be possible to string together as many of those as you want, with no artificial limits like "energy" or whatever that a lot of mobile games seem to do.
So far, I've experimented with prototyping an RPG with a sort of "match 3" based battle system, and more recently have been working on an idea where the gameplay / battle system would be kinda vaguely inspired by Tetris, though that's still in the super early stages.
Anyway I think that about sums up my general ideas / philosophies on all this, which got pretty long (although, this is making me really appreciate the higher character limit on here -- I keep thinking what an awkward mess of multi-tweet threads it would take to have this kind of exchange on Twitter haha)