You have it right, Patrick; antenna gain comes before amplification. For a ham, money spent on a 3el yagi is better than a linear amp. But for TV reception, adding a preamp near the antenna not only compensates for distribution losses, it makes it possible to receive weaker signals than without a preamp.
Every reception location is unique and requires a custom solution. May we see your tvfool report to suggest the best UHF high gain antennas?
For a UHF only antenna the Antennas Direct 91XG and the DB8e with both panels aimed in the same direction do quite well. If you need a VHF-high/UHF combo the Winegard HD7698P does well.
W4...
ex W2...
ex DL4..