FUE candidate - Hairline too low? (photos)

FUE is just a harvesting method.  It does not relate to results.  If you want a surgical recommendation you need an exam first.  You need to see a doctor to better understand realistic expectations.

Hairlines tend to elevate naturally as you age.  One might say that you have a mature hairline currently.  You can certainly lower the hairline to the point you desire.   However, this is going to be a permanent decision if you make it.  You still might loose hair later on in life, which will require you to fill in behind this hairline location.  That means more work later on.  Also, if you have loss in the crown later on, the low hairline may not look appropriate for your age and degree of hair loss.  You should consider your age and family history for hair loss when making this decision.  Also, the only way to truly evaluate the potential for crown hair loss is to compare the cross sectional trichometry in the donor area to the crown, top, and front.  If the number is lower in the crown or top than in the donor area, you can bet that you are going to have crown hair loss.  There are not many physicians who do this test because it costs money to do the test.  Finally, you need to find a good physician to build this for you.  You can't reverse what you are considering easily if the work is poorly performed.  

I don't see a problem here with the height of the hairline that you are looking for. It is a little flat, and I would suggest raising the sides up slightly, but that's not a huge issue. The biggest concern here is ensuring that hair loss later in your life won't make the transplant look awkward, but without knowing your actual age or family history it perhaps could be a non issue for you.