Personally I don't see the point in an iMac. Might as well just get a laptop and connect it to a monitor if required IMO.
Why don't you actually give it a go and find out, and compare the costs along the way. IMO a lot of Apple gear is priced at a premium, yet somehow the iMac has found a niche / comfortable point. Spec an i9 laptop and a 5k display, and then benchmark the results. I'm more than happy with my iMac on performance alone, let alone the other benefits.