In the meantime, how do you look at adding RPG elements to the game?
Let's say this:
-Small character upgrade (more inventory slots, faster sliding rollback)
-Unique drop from enemies, for example things that cannot be created, but can be obtained by killing enemies.
-Upgrade automation machines for some unique things dropped from enemies, for example, the heart of a robot (of course, this is something like a mini-battery). I came up with this thing as a replacement for the well-known tiers in such games. Like tier 1, tier 2 and so on.
-Maybe rarity of items? But this one need's to thinking..
...
Something else? There are many ideas, but not all of them can please everyone.