Wow, good analysis, recommended. What a director.
Lighting for slo-mo when using high frame rates, and how to avoid flicker from combining different light sources.
I have a business that does motion graphics, 3D and live action and using the iMac has been good for me. It's not perfect - I've crashed the thing MANY, MANY times in the last month, but I do push it pretty hard. Also if you have iphone, ipad etc then using mac makes sense. Adobe's apps only run on Mac or Windows so those are your 2 choices. I would have no problem switching to Windows, the only thing stopping me is that I feel I would take a productivity hit in the short term because I'd have to learn a new system. Ideally I'd like to use Linux but none of the pro apps I use daily run on it (apart from Blender which I'd definitely classify as a pro app!). So to answer your question the iMac will be fantastic for what you want to do. Word of advice - go large on the specs. It costs more, but it's worth it. Go for solid-state hard drive (flash storage) and get lots of RAM. I had a recent iMac but it didn't have the fast storage or RAM and it drove me up the wall; those two things make a lot of difference