Welcome and congrats on your new HTT. Yes having you own full washroom on board is great as are many of the other features that come with your new HTT.
Keep one thing in mind, a HTT will suffur from some of the same heat loss problems a PUP does via the bunk ends.
Invest in some Refectix for your bunk windows and some Popup Gizmos
for the top of the bunk ends and you'll have a much easier time heating and keeping warm.
That said, you say you bought in Texas so I assume you are from there as well. As a Canadian I can't help myself in asking this question but, how cold does it really get there? I've camped down to -20 C (-4 F), how bad can it be in TX
? Congrats again.