He knows how to thermoregulate so I would let him do his own moving around in the tub. If you want to heat the area around the tub, I would recommend using this with your space heater: http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1 or try other options for keeping it warm. If the ambient temp dips into the mid 70s that is fine.
As for bombarding us - bombard away. You accepted that you're new and have learning to do and are reaching out for advice and suggestions on how to improve. Lots of people here are very eager to help people that want to be helped and are receptive to criticism and advice.