I suggest you wait until you get all of your admission decisions, financial awards, honors college decisions in – then, if possible, revisit your top choices before making a choice. It is great that you have affordable options already in hand.
FWIW I don’t think there is a notable prestige difference between UA and UTK. And I would not be too concerned about seeing HS classmates at UTK – it is a large enough school that you can forge your own path and develop new relationships.