The problem with your "different uniforms for jammers" idea is that it would either eliminate jack of all trades skaters or force breaks for uniform changes.
I have a friend who skated old school derby professionally for decades. He wants different colored helmets for jammers like they did.
If you watch any old school derby video, you'll see helmets falling off constantly. Swapping a helmet between multiple skaters tends to lead to it fitting nobody correctly or just not being properly strapped.
The problem with your "different uniforms for jammers" idea is that it would either eliminate jack of all trades skaters or force breaks for uniform changes.
I have a friend who skated old school derby professionally for decades. He wants different colored helmets for jammers like they did.
If you watch any old school derby video, you'll see helmets falling off constantly. Swapping a helmet between multiple skaters tends to lead to it fitting nobody correctly or just not being properly strapped.