Yeah, i think the 3 different designs for each class would be a good idea. The design you did most recently is more suited to the engineer personally. However, if you were to incorporate this, i can agree with you and say that it will take much longer.

Just try and find individual unique features you would spot on each class and merge them with this design. Such as the arb sets are different with each class or even the ‘legendary’ armor: Sur-manx, Tek’Graval etc..

Just an idea, maybe you can justify your own opinion since your designing them