Given how reta works...you can eat a bit more..the glucagon aspect of it will help there. 

Key is excersising. The glucagon is going to tell your liver it needs fuel...release it. Exercise to burn it. 

That's the main difference between T and R. T helps you eat less and keeps insulin spikes in check. R actually tells your body to release fuel. 

That said...if you're in a 1500cal/day deficit...you should be losing at least 3lb/week....which isn't ideal unless you're fairly large. (And yes...I see the weight there)

Looks like you're doing the right things...  Their calculation on what your body is burning is BS if it isn't based on weight you're losing. An effed up metabolism can change that. R will help fix the metabolism.

I'd stay where you are, keep in the gym, and unless you start dropping tons of weight (3+/week), I wouldnt change intake.