I think it’s goes as said that you need to work out your maintainance calories before you decide on a deficit otherwise what is it a deficit of? There are some pretty accurate calculators for working out what your maintainace calorie intake should be.
I lost 5kg (about 10lbs) at the begining of this year and gained 30w on my FTP over a 3 month period.
im 34 (80kg) and also aim for 1900 calories + workouts, on average im eating 2500-300 callories a day and have lost 1-2lbs a week for the past 6 weeks.
I had a DEXA scan last week and am at 14% body fat, so was overweight to start with which is another factor, the higher your body fat the easier and less detrimenal to your performance it will be to loose weight.
But if you are going to have a deficit while building you do have to be careful with meal timing and Macros making sure you are fueling and recovering well by eating the right stuff at the right time.
Having a power meter and knowing the kj you are going to put out in any given workout really helps to fuel and recover well too.