I managed to finish Nitocris' skills before Lostbelt 7 of Part 1, and the reason for this is that there may be a mission where you will be forced to use Nitocris' skill 8/8/8 or your Nitocris.

Next year after I finish leveling Illya's Caster and Archer Class to level 100, I was thinking about taking care of BB Summer and Meltryllis' skills.

I hope Nitocris can solo alone without using Servant Support.