Welcome! Your games have such a unique feel and a joy to play.

the 3D math was a struggle, I still need to program a bit further because some 3D elements (such as the vectors and text and lines) are drawn with a 2D graphics API which does not generate depth information.

For healers it is typically the repetition, it is seen as a more passive type, necessary but not fun. Hybrid classes on the other hand can take part in the action, but the game needs to be balanced around the fact that there is not a dedicated healer for a tank for example.