Thanks for the comment! I always appreciate constructive criticism. I'm glad you enjoyed the game on the whole. I'm definitely not a graphic artist and am better (in my opinion) at music and world-building, which seemed to be the parts you enjoyed the most.
Some or most of the full heals that I put into the game were to prevent crashes or to make hard boss fights easier. Whenever the party shuffles around, there's a risk of game crash if Tilda is KO'd. For instance, if the party shifts from Tilda / Huppo / Phede / Posh to Tilda / Mendy / Sloppy / Rumor and Tilda happened to be KO'd, this would lead to a random game over screen. The simplest way to fix this was to just admit defeat and full heal the party before swapping everyone out. Maybe a better programmer could have figured it out, but, alas...
As for the ending: Did you max out the bond with Huppo? You need that to get the best ending. Huppo, Phede, Omen, Guuchi and Sloppy all have "ults" that they learn when their bonds are maxed out, and you need all those to get the good ending.
Thanks again for playing. <3