A decent CPU and adequate graphics is usually all I need in a laptop while traveling, but it would be nice to be able to plug in a more beefy GPU at home to play games and drive more monitors at higher resolutions.
Well, Thunderbolt 3 now explicitly supports them (previously Intel wouldn't certify for what appeared to be non-technical reasons), so it might actually catch on.
I don't expect it to be cheap; but even if the chassis is a few hundred dollars, if you can reuse them for three generations of GPU and laptop, it's probably worth it.
A decent CPU and adequate graphics is usually all I need in a laptop while traveling, but it would be nice to be able to plug in a more beefy GPU at home to play games and drive more monitors at higher resolutions.