Just a personal account from me, I won't claim to have any
knowledge of exercise or nutrition.
For me striking a 200KCal deficit for a weekly average
worked well; trying to reduce food intake drastically while
exercising lots had me tired, frustrated, and not really losing
weight fast enough, either.
A slow but steady average deficit, mixed up of days w/ spikes
(allowing myself 300 over), and making sure that the intake
remained irregular (no patterns), w/ a variety of exercise, HIIT
on both weights and running, cross trainer & rower, w/ weights
proper I lost almost 20Kg in just under a year, gained muscle and am
overall pretty fit and happy atm. Just hang in there. W/ my
own regime I lost an average of only 400g a week, but found
the lifestyle change doable.