If the room stays that warm you might not even need a RHP. Fluorescent lights + flexwatt should be enough.

The floorboards won't cause humidity issues inside the T8, These cages hold humidity in extremely well.

I would start off by getting a T8 with flexwatt and 2 fluorescent lights installed. Get it set up then see if you need anything more. my guess is that you won't. If you do you can always add a RHP later.