This really is the way forward. Laptop docks are very affordable now. The laptops themselves can be ordered with powerful graphics cards for video editing or gaming. The cons that I have seen are repair/upgradeability, heat, and noise.
My current laptop when gaming and all settings cranked has a large amount of fan noise due to the need to remove so much heat in a hurry. Smaller components in a small form factor make a lot of heat. However with the system set to silent and it throttling the processor in favor of lower fan noise the computer is inaudible.
Given the Pros and Cons I would rather have the option of taking the machine anywhere in the house or on vacation and also docking it when needed to have access to multiple monitors and a proper work area.