Thank you for the photos. Yes, a hair transplant can fill in the hairline and even lower it a bit. We use NeoGraft, automated FUE, to avoid the linear scar across the back of the head with strip method. For patients under 25, I often recommend that they consider Propecia and Rogaine before jumping into a HT.
Either FUT or FUT are acceptable methods. FUE would be slightly favoured as you don't need many grafts and it can help avoid a linear scar.
If willing, it would be terrific to try non-surgical treatments (such as minoxidil and/or finasteride) first. There do help in the front too. If it turned out that you were a grear responder to these treatment it could delay the need for surgical restoration.
What a great head of hair you have!
FUE and FUG are both great treatment options for you but you should also be taking steps to keep the rest of the hair from thinning.
It appears you have quite a few miniaturized hairs in the hairline that could be turned back to a good strong healthy hair with Capillus 272, which would make your hair look thicker in the front.
FUE and FUT are just harvesting methods and it relates to donor scarring. It is not related to hair line lowering. If your exam shows no genetic balding, then you can probably have any type of procedure to alter your hair line.
Hair line lowering can be successful if done by an experienced doctor. The art of designing the hairline area and using the right technique is very important to give it a dense and natural look which would blend in with the rest of your hair. You can do wither techniqe for harvesting but most important is the recipient area design to get the natural result.
Hairline lowering in men should be done with hair transplants, not the surgical alternative as many young men will bald above the transplants so hair transplants are needed to be able to follow any balding that occurs. We have done thousands of men with this, see web reference below for pictures
It appears that your high hairline is due to male pattern loss. FUE or FUT will work for you. With your hairstyle, strip harvesting of donor material (FUT) would be more cost effective. However, if you were ever to consider a surgical hairline lowering type of procedure be sure that grafting done before after that procedure is with FUE harvesting.