I mean how can it be that a soldier in heavy or full plate armor runs as fast and even longer as a clothie ?
about rangers : ranger with maxed out "nimble" run like usain bolt even though wearing medium armor..
in my opinion every gear part should have a speed multiplyer ( at least helmet , chestguard, legguards and shoes maybe).
Starting with x1.0 if being naked
0.95 for cloth and 0.9 for light gear for example. If you wear 1 part of each the calc should be like 1x0.95 + 1x0.9 = 1.85 -> 1.85:2 = 0.925 which is your run speed then
I think a system like this wouldnt be hard to make and balance classes a bit .