I'm suddenly having flashbacks to Chrono Trigger and Chrono Cross.


Okay, some of the ideas you have here under the "new game+" umbrella... I can get behind them. Things like being able to have a slider for "easier > normal > harder" of some sort (maybe in the advanced settings when starting the game), and the ability to fast forward time (freezing time is called "pausing") would be interesting.
...but some of them? The ability to give infinite gifts, rewinding time, infinite hp/energy, insta-grow crops? I think that belongs in the realm of mods.
Now, how do you determine when you can "new game+", though? How do you "win" at Stardew Valley? There's no real end of the game, which is usually how "new game+" mechanics work. The closest I can think that the game has at this point is "perfection". So, are you thinking something like that, where if you have 100% perfection in one of your saves you can "new game+"?