13" MacBook Pro as a desktop

[dazzer21-2]

I want a machine to supplement my late '15 iMac 27". I need a laptop so I'm thinking along the lines of a MacBook Pro with a dock and external display. Potentially, this could be an all-day machine, used for, in the main Adobe Creative Suite, but I'm seeking people's experience with what it's like in terms of outright reliability and its suitability for dealing with a hard day's work, day in, day out. All of my iMacs have performed flawlessly for my needs, my main 27" handles the stuff I do with ease, although on odd occasions lately, the fans have audibly kicked in which they never used to do, I'll put that down to warm weather for now. What is it like in terms of heat generation? I intend to add some sort of hub, maybe one of the Satechi ones, and it will drive an external screen, probably a 4k at around about the size I'm used to with the iMac. The thing is, I'm either drawn to mid-range 13" or bottom of the range 16". The larger screen would be useful when used on its own, having been used to a 15" MacBook pro some time previously, but I need to be sure that there is a level of overhead that will make it more futureproof later on. I know Apple Silicon is coming along and that makes this more of a difficult decision to make, but I really do need a second desktop and the added flexibility of having portability is a bit of a draw. What do you think? Thanks.