I would also appreciate it if some skills are moved to "optional" sidepaths. I often have to get skill, which have no use to me, just to finally get the one i like.

For example in the "Melee" Tree, just make all the "Main" Paths to the center %dmg, crit or the like and put everything else on the sidepaths.

The Capstone skills could definitely use a slight graphical tweak.

Due to the design of many of trees, it can actually be difficult to tell where the capstone even is, and I do not remember seeing anything that specifically informs the user that they need to complete the entire tree in order to unlock the capstone.