Hello and welcome…
You have so many partially leveled.
Now, next project focus one by one on-color rainbow level, so until one hero finish then next hero on that color. Red feeder to red hero, etc.
Red: Boldtusk ASAP, Wilbur, Falcon, Scarlett, Colen
Blue: Grimm, Sonya, Triton
Green: Hansel, Melendor, Gadeirus, Skittleskull
Yellow: finish Chao, Li Xiu 3.60, Wu Kong not so urgent you have Ranvir and Miki, finish Hu tao.
Purple: Proteus ASAP, Rigard
And also consider leveling *3 worth to keep:
Red: Rudolph, Squire Wabbit, Namahage, Hawkmoon, Nashgar, Azar, Jahangir
Blue: Gato, Valen, Ulmer, Gunnar
Green: Muggy, Belith, Brienne, Berden, Mnesseus, Hisan
Yellow: Bane, Melia, Kailani, Gan Ju, Arman
Purple: Balthazar, Gill-Ra, Chochin, Tyrum