The Hori Nintendo Switch Game Card Case includes 24 Game Card Slots and is able to hold 2 micro sd cards. Given that the sd card slot is of easy access behind the kickstand if you ever needed extra space would you obtain and use multiple micro sd cards?

Source: https://www.amazon.com/HORI-Game-Nintendo-Switch-Officially-Licensed/dp/B01NASY99Z

Depends if they hotplug of if you have to power down the Switch to switch the SD-cards (like most other mobile/portable devices).

No. I will hope that a single 256GB card will be enough. Considering it's a Nintendo console, I suspect I won't have to worry about having too many big games to play. So I should have plenty room enough with such a SD card.

Depends how it works. On the 3DS switching SD cards is a major pain in the ass. Hopefully they streamlined the process.

Well there isn't usually pre-installs on Nintendo systems, so storage needs are far lower than other consoles, so one 125GB or 256GB card will suffice for sometime

I can get a micro SD 128GB for less than 50 €. So, buying multiple could be possible. Labeling them would be a pain, tough :/
But, I will consider it, when the time will come.

Most likely. Thats how I did on my Wii U (I got like 3 32GB USBs lol)

I won't use any, I'll buy almost everything I can physically and hope 32gb is enough for DLC. I'll only be buying exclusives on it so it should be.

Due to the potential for their being multiple Switches in my house, I'll be getting most games physical. Will likely get 1 64GB SD card just incase.

I hope Nintendo allows us to back up games on PC or an external drive connected to the dock. That would be fine for me and the same way I manage Vita games. I'd probably choose something like a 128GB or maybe 256GB Micro SD and then just swap games out. I'll probably also tend to use it for exclusives only to reduce the amount of storage I need.