When the game developer tells you not to expect the "finished" product on release, you know the game is finished before its even released.
The user interface is terrible, inventory management is terrible, quality of life is terrible, end-game is terrible, and the list goes on and on. Just visit their official forums and see how many negative posts there are.
They said they will listen to feedback from players and implement them. Separate inventory space for gems? Season 2. Leaderboard? Season 3. Do they really need at least half a year to implement such minor changes?
I would recommend you to purchase the game few years down the road when it is on christmas sale for 10 bucks. That way you get to save and play the game when it is more "complete".