Hair transplants or Hairline lowering or both?

The best thing is to find a doctor for a personal consultation. You need an examination of your scalp and understanding of risks with realistic goals/expectations. 
One risk is that forehead reduction surgery leaves a scar on the hairline no matter which surgeon or type of surgery performed. However, most of these scars are not as noticeable depending on how the individual heals. One limitation is that it does not round out the face (temple corners).
Hair transplant surgery may be an option for a forehead reduction.  It actually can give you a natural and soft hair line as well as rounding of the temple corners.  Hair transplant surgery limitation is that the results are not immediate and the growth will not be as "full" as a forehead reduction surgery.  
You can see examples of hair transplant surgery results in the VIDEO.

Lowering the hairline is done by making a carefully placed and camouflaged incision along the hairline and used to advance the hair bearing scalp and shorten the forehead in one surgical procedure. This technique can result in hairline advancements typically in the range of 1.5-2.5 cm and sometimes more. Based on the photos provided, I think this is a totally reasonable goal. In fact, I think the ideal way to complete the most natural-looking forehead reduction is to perform the scalp advancement portion first and then come back and place strategic hair transplants for the best results!
Another option for hairline lowering is hair transplant alone, which can be performed to lower the hairline. Hairline lowering with hair transplant does not require any linear incisions along the hairline, but does not usually attain the same density as a hairline advancement procedure with only one hair transplant session. In most cases, patients will opt for a second hair transplant session about one year after the first session in order to achieve even greater density in the transplanted zone. Once this second session is complete, patients have usually achieved excellent density. 
In some cases, patients will choose to combine the two techniques.
I would advise finding an advanced hair restoration surgeon to discuss options and receive a full evaluation.
All the best,

Thanks for sharing your photos.  Based on what you have drawn out, I think this is a very reasonable goal!  How much advancement I can get depends on how loose each patient's scalp is, and the only way to determine that is with an in person physical exam.  In general, I can usually advance the scalp 2-3 cm and sometimes more!  It's a great option for a very dramatic difference right away.   FUE transplants can be used to reshape the hairline and/or advance it further if needed. Best of luck,Dr Rodman