Question regarding my incoming Thor

So years before I decided to get a Thor, I decided to mod my Wii U for emulation purposes. I got all of the games from the nes, snes, every game boy version, sega genesis, n64, and select GameCube and Wii games all loaded onto a 256 gb as card. Basically, any games I wanna play that are not DS/3DS games.
I ordered the ayn Thor Max 512. Even so, I decided to buy a cheap 256 by micro and card for bigger games I may wanna get. It was like $15 from Walmart. My question is, when that card arrives, should I start transferring all of my roms to that micro sd card as well as downloading the emulators so they can all be simply transferred to my Thor when it finally arrives, or should I wait?