if im honest, when it comes to starting off making characters for Ue4, i will say, just make a basic character mode, Rigg it and get it moving, that way you can cover your animations and start developing mechanics faster… Then you can design and build your character around the mechanics…
I suggest using Make human to give your self a base mesh, then use the blender .mhx importer to move over to Blender which will give you allot more freedom to move forward with.
But Never use a preset rigg build around rotation’s, IK’s make animations significantly faster and look allot smother in the end