It's hard to tell how your hair looks based on your photos if you've done a comb over. Again, it would be a mistake to stop finasteride, lose more hair on top and then have a transplant, in part, to replace that hair. If your doctor won't prescribe finasteride for you, then change your doctor. If you're not having an adverse reaction to the drug, I don't understand where your doctor is coming from. You need to plan for the long term, having hair that looks acceptable to you, into your 60s and 70s, considering where you are now and what you have left in your donor. Of course your family history of hair loss is a big factor.