Alright, so I drew up my ideas for what the avatar should look like. I took inspiration from both the regular Blockhead avatar from BL, which has at least nine customizable parts, and the new R15 avatar from ROBLOX with at least 15.

The final design is boxed at the bottom right.
I took a lot of cues from Trogtor's avatar idea because it looked so clean-cut and cute. I didn't agree with full arms though; they just seemed awkward. So instead, I looked to the R15 avatar and to the BL avatar and I combined them into an arm with floating parts, like the BL avatar but with another small part in between to signify arms. I did the same with the legs. This means that you can differentiate between jackets, t-shirts, jeans, and shorts without the arms and legs seeming stiff and stocky.
People were complaining that the stud on Trog's model was awkward, so I flattened it out. I also took inspiration from the shape of Trog's torso, combined with the anatomy of R15's torso, and combined it into a torso with upper and lower parts. These can't move independently from one another; that'd look weird. Instead, the torso twists at the waist, which is something else I took from Trog's design. Instead of a single piece like with Trog's, as I said earlier, I separated it into three parts; the foot, the leg, and the asscheek.
I also threw around some ideas about customization anatomy-wise. Because of the two-part torso, you could basically make it so that your character has a BMI. I also thought of an idea utilized for at least some time by ROBLOX where you could customize the shape of your head. And I couldn't finish the design of the character off without making some Blocko feet.
After I finished with the design of the avatar, I threw around some ideas on studs for the game. That came out pretty "bleh" though so you can just ignore that. The avatar design is subject to any changes people want to make.