That's how it's supposed to come out. Roller wax is dispersed as a thin film which is always consistent because of the machine. The spatula depends on your use and experience, how much wax you picked up, how you apply etc. in time and after practice that too will come thinly, as thick patches don't really work too well
As for temperature, when it comes to rolls you are indeed right that when it's got the proper temperature it will roll easily. Also, most roller machines won't allow the wax to get too hot so you don't risk getting burnings. It's usually just a tiny led light that when it goes off or green (depending on your machine) then your wax is ready to be used.
Not sure what you mean about use again? Once heated a roller will take some time before it cools down because even though you take it out of the power cord, its case is still hot and it keeps the wax likewise. So yes it can be used again. You don't have to plug it in and out for every single strip you make. On the other hand, when you pick up spatula wax, the quantity is so small and it comes in direct contact with the air that it cools down immediately. Is that what you were asking?
Just a tip. If you are going mobile, make sure you preheat your wax to save yourself some time
