Is this a FE card

Yep, I have the 12 pin side done with those absurdly small crimps (used an Iwiss SN-48B left side middle hole as seen by holding with right hand for a near perfect crimp over 18awg wire coating), I put some (sadly on the thin side showing the texture underneath) heatshrink over the melted ends butted up against the connector here since the wire+sleeving won't even come close to fitting in the pin hole. Not as clean looking as that telios whatever stuff on the rtx 12 pin I've seen done here, but I don't think it's too terrible for a first timer doing this. I guess I can just tell myself the heatshrink is added strain relief, haha. I can depin the psu side and put the comb through that way when I'm ready to put combs on.

Paracord is a bit more prone to “bulking up” if you overmelt it

I think I know what you're talking about, I use a hot air rework station with a small tip, not a flame/heatshrink to compress it, so I can just pinch and roll the end that's curling out real quick (its hot!) then trim any excess junk that goes over the crimped end with an exacto/hobby knife. It looks ugly like this without any heatshrink over it.

I reckon you would be fine with most of the combs you mentioned above.

I guess I'll have to yolo it when some of the 'stealth' closed acrylic white items comes back in stock, or settle for the OverkillPC's aluminum in 'silver' color.

The SN-48B is for 26-16AWG wire.

This is a popular replacement for the CTX. I don’t own one but I’ve seen it recommended.