Here's my work in progress tier list:
Some notes:
Obviously when transitioning to any tier, you try to prioritize the better characters. I now have over half the 4* tier champed (33/57). Out of curiosity I wanted to see how many of each tier I have champed.
Top: 4/4 (100%)
Primary: 5/6 (83%)
Secondary: 16/23 (69.5%)
Tertiary: 7/19 (36.8%)
Bottom: 1/4 (25%)
Glad to see the percentages steadily drop as I move from top to bottom.