What about this one: 2019 C10 100% Original ez Share WiFi sd Card Memory Card Sdxc Card for Camera Transfer Pictures and Videos by WiFi (32G) https://www.amazon.com/dp/B07SPBNNJY/ref=cm_sw_r_cp_api_i_WDUlFbSQXPHYC

V 2.5 will work fine. The serial line will come with the advantage of being able to send data back the PC making debugging things a little bit easier. It is also easier to load new roms over usb so you don't need to be constant swapping sd card.
If you decide to stay with 2.5, which will probably work just fine for you, you can get a wifi sd card it will make the development cycle must faster
https://www.amazon.com/Original-Memory-Camera-Transfer-Pictures/dp/B07SPBNNJY/ref=sr_1_3?dchild=1&keywords=wifi+sd+card&qid=1597870754&sr=8-3
It will let you transfer roms to the sd card without having to remove the card making the dev cycle much easier.

As for emulation I would recommend you use cen64 for testing. I typically jump back and fourth between cen64 and real hardware. It is easier run an emulator but obviously isn't as accurate. I would also recommend Project64 for it's built in assembly debugger. I would not recommend Project64 for it's emulation accuracy.