Heat for Baby

[snakeophile]

I have a 4 month old jungle x coastal housed in an exo terra 1 foot cube. Heat is supplied by a herpstat2 driving a UTH mat (under a hide) and an overhead ceramic heat emitter. She seems to prefer to roost under the emitter. My questions are:
1> Do ceramic heat emitters benefit from proportional controllers or do they just turn on and off. I ask because the drive percentage is either 0 or mid 80 % while the heat mat ramps up very smoothly.
2> Should I keep the heat mat on so she can keep warm when she chooses to hide (seldom)
3> What is the recommended temperature for a hotspot for a 4 month old of this particular mix.

Thanks.