Egg retrieval or FET!?

So, we did an egg retrieval (my 3rd) in March and froze the 5 fertilized embryos and 2 came back normal - I turned 40 in April - transferred one normal male embryo on May 8th and got a BFP but miscarried at 8 weeks. We have one more Normal PGS TESTED embryo ( grade 5AA) to transfer.

NOW, I am completely torn with this question : should we transfer the existing frozen embryo or go for another egg retrieval to bank more embryos just in case 1) this embryo is also not successful

2) if embryo implants successfully and I am able to carry to term, I will be 42 before I can do another cycle and by that time my eggs will be more deteriorated in quality - 40 is better than 42 ( we are hoping to have at least 2 babies with god's blessings)

OR should we transfer the one we have and be happy that God allowed us to have at least one child !?