If you need to push performance you'd probably go for a Mac Studio, no? Or at least a Mini.
This is basically 99% of the proposition of the iMac at this point. If you don't need the specific all-in-one, color, and other design aspects of the iMac or can afford a Studio display, there's no reason not to buy some other display + a Mac mini or a laptop + display
If you need portability, you have your phone already.
I did have a 2010 Mac mini server, don't remember how it compared to the non-server one other than having dual HDDs instead of the DVD drive. I put them in RAID-1.