Copy more features from the rune factory/hm games? for example, having monsters be tameable and can tend to your farm, being able to charge tools so they effect a wider radius, does the game have a rune point/fatigue system where you can only do so much per day? (or if its like rune factory 3 where u can eat food to regain rp).
We actually did have a big discussion on tameable monsters. CA didn't confirm or deny anything on it, I think.