The problem with just relying on USB-C Thunderbolt "docks" is that I've found the cost-effective ones (30-60$) make the computer work really hard and get hot, make the dock hot as well, and give some occasional lag on wired mouses (extremely annoying). I tried around 5 of them with my X1 Carbon (returned all), and ended up making my own ghetto-dock by encasing all plugged-in cords in thermal plastic (luckily the X1C is flush in ports on the left side), because Lenovo's dock was absurdly expensive, but probably worked a lot better as it has power supply and used both USB-C ports. There are probably great 3rd party powered docks that work with multiple laptop brands, but they're going to be quite expensive as well.
I just got a Surface Laptop from work, and the connect port / dock works great - very secure but easy-to-disconnect port (magnetic), and the computer and dock stay cool. I bought another one for home use for $110 open box. You're not going to find a powered 3rd party usb-c dock (surface laptop now has usb-c on the left side of course), that will work as well as the Surface dock at that price point IMO (or even at normal non-MS vendor price $150 new).
Unless you REALLY need to use the same dock for a Surface and non-surface computer, I see no compelling reason to not go with the connect dock for surface. And if you must go USB-C dock, don't cheap out....if it's under $100 and non-powered, probably will give you some issues (hot computer, not good) if you tax it with external monitors and peripherals.