I can't help with the hair loss or A1C, but I can tell you about the last 20 lbs, how that was for me. It was HARD. I had to commit to hand to hand combat with each of those pounds. Here's what I did:
--very strict eating regimen. I stayed under 1100 calories per day, no exceptions. Three small meals and no snacks other than protein shakes. No grains, no starchy veggies, no sweets, no tropical fruits, and no liquid calories other than protein shakes. NO EXCEPTIONS to any of this, no "small quantity of good food and occasionally more carbs" -- that's how people in maintenance get to eat, not people trying to lose the last 20 lbs.
--weigh or measure virtually all portions and track religiously -- fanatically even -- on MyFitnessPal.
--vigorous exercise at least 5 days per week, 30 minutes per day, but do not count calories burned or give yourself permission to "eat back" calories burned. Exercise for me had to include a mix of different types: HIIT, running, circuit training, weights.
--if my weight stayed the same for two weeks, I switched over to 5/2 eating for two weeks and that would get the scale moving again.
Good luck!