So getting a 3rd Gen Scarlett at the moment is quite difficult, the 2i2 seems to be sold out everywhere I look.

I'm looking at the Solid State Logic SSL2 ($369) instead. Happy to hear any thoughts on this.

For microphone I've kind of narrowed down to a few options.

Condenser:

Rode NT-1 (flatter frequency response than the NT-1A), $339 but includes shock mount, pop filter and cable.

Audio Technica AT2020, $129

Dynamic:

Shure SM57, $179
Sennheiser e609, $119

Ribbon:

Golden Age R1 Mk II, $279