I have come to this rather tardily I fear, but here are my suggestions if it is not too late.
I am not very artistic on a computer screen but in this case, I thought it might come out better for the symmetry if I used a gimp.
I really liked the idea of the 3 "semi-circles above" but think it is still too similar to Ubuntu. I thought also that 4 U-people might represent Coders, Translators, Testers, &Users which is the community of UBports. By having the heads half in, half out of the containing circle, I think it represents that we look to each other as well as to the rest of the world at large.
A major improvement to the design would be edging to the characters and circle, particularly on the last (Yumi badge) design so that it could be just the white parts and the edging without the background red.