What testing would you do before transferring a euploid?

I’m thinking of doing some testing ahead of doing a transfer of euploid embryos as I have unexplained infertility, and if I can, I’d like to find a reason for the infertility before transfer so we can max the chances of success. Anyone done this or have any thoughts on doing this?

My doctor thinks it’s overkill and I should just try a transfer because "95% of euploid transfers work by the 3rd try" but I don’t want to waste precious embryos if there’s something we can fix beforehand.

It'll be my first transfer of a euploid but I did transfer an untested embryo in summer, ended in a miscarriage. This is why I'm doing PGTA testing despite being only 30 - I don't want to risk the heartbreak and wasted time by another miscarriage.

By testing I mean things like Fertilysis or ScreenMe for vaginal or uterine microbiome , or any blood test (should I do NK cells?).

I have a child, conceived naturally, 3yo. I am 30yo.