Not only are you making difficult decisions but you are sharing your decision making with us in a way that can only help others. Thank you.
I have never had to make this decision as I had a lumpectomy 3 years ago.
I would speak with the plastic surgeon and ask him/her how likely it is that the two reconstructed breasts will be as much of a match as you hope they will be. You would be giving up something very important to get that match and if you didn't get the match that would be difficult.
My breasts clearly don't match as I lost a bigish chunk of one and not the other. I have come to not mind that much. I wear a prosthesis when it is important.
I am answering your post because breast sensation is important to me too. If I have a recurrence and have to have a mastectomy I'd be glad to have one left with feeling.
Also I have a friend who had her non cancer breast reconstructed to match her reconstructed mastectomy breast and she is very disappointed- and angry. She went to a well respected plastic surgeon and had it done because that was important to her. She says they don't match. I don't know how they look. It isn't obvious from the outside but it is clearly not what she hoped it would be.
I would be direct with the plastic surgeon and tell him, as you did us, that you'd be giving up something you cherish to have them match and ask what his level of confidence is that you will get what you want.
Best of luck and hugs,