External ethernet over TB3 is also a thing. Honestly, all these "what about" things are doable over TB3, with the exception of a CPU upgrade and Optane (I'm ass

External ethernet over TB3 is also a thing. Honestly, all these "what about" things are doable over TB3, with the exception of a CPU upgrade and Optane (I'm assuming TB3 doesn't quite give you that level of latency). So, as far as expandability I don't think it is that bad. The only question is whether you want a carefully designed machine like the iMac surrounded by a sea of dongles and enclosures.