You don't need to worry about the system changing up again - its current incarnation is permanent now. I've spent far too much time on it as it is and it was only ever supposed to be a thematic addition and not a whole other game in its own right.
As for the RNG thing, which I hear now and again:
1. All systems must have RNG built in or they become simply a mathematical formula, like the old system was, completely devoid of strategy or nervous tension.
2. The current system has SO MANY ways to influence the dice rolls in your favour. Meals, Tactics, Elixirs, Upgrading Dice, Powers - and the next update introduces "Daily Buffs". It's RNG dependent only if you're not preparing beforehand. The exception to this is the first two fights, but those are supposed to cause you problems because if you start out as superman where the heck do you go from there?
It is, unfortunately, impossible to please all of the people all of the time; there's no system on the planet that everyone is going to like, and sadly you fall into the "don't like it" pool this time.
The best I can do as a solo dev is to make something that's as thematically consistent with the rest of the game as possible, doesn't take too much time to implement (so I can focus on content), and finally to provide a way to skip the combat entirely for the players that don't want to engage with it.