Steps in Rigging / Animating workflow, and Custom Shapes

OK so I am brand new to Blender, been fiddling for a couple of months but only starting to put more time in lately. I’m also pretty new to using Forums in general so I hope I have posted in the right area? Anyway moving on I have 2 questions:

  1. I am Rigging and Animating box shaped humanoids just to learn the process more than anything else as it is a good way to learn. I’ve created, rigged and animated the same looking box robot at least a dozens times to reinforced what I have learnt.

The question is, in many tutorials I have watched people create the mesh, detail it and then assign a armature and animate from there. Could you create the Mesh, Rig, Animate then go back and detail? I realise that there are likely many reasons you wouldn’t in soft edged / organic models, but I can’t help thinking that in hard edged models you could do this?

  1. In a couple of videos on Rigging / Animating I have watched, the tutor substitutes the Octahedral bones using custom shapes, often a circle, and I am having huge problems substituting in the circle with the right rotation, size, and so on. Is this a technique I should really push hard on learning over the next couple of weeks or it is not that important? I can see the value in it, but I am wondering if there are any other tricks of trade I should be aware of that could make it easier?

Finally if anyone is wondering, no I am not using Rigify as I want to understand the process of rigging especially when I start animating non-humanoid shapes.