A healthy calorie deficit to lose weight is about 10-20% of one's current calories intake. A 2,000 calorie a day consumer should have about 1600-1800 a day.
Good job, OP. You're certainly doing better than me regarding diet. Due to the fact I'm bulking (gaining muscle) rather than cutting (losing fat), I'm less strict about eating unhealthy, but still generally try to eat a healthy, balanced diet.
Strength training is a good idea to maintain muscle. Working out isn't as hard as one might think, and only needs to be done maybe three times a week to maintain muscle.
I also advise to calculate not just calories but macro and micronutrients as well, if you aren't already. These are the daily nutrients your body requires. Macronutrients include Protein, Carbohydrates, Fats, etc. and Micronutrients are your vitamins, minerals, etc.
Also, things such as Fats and Sugar are NOT bad for you, in reasonable amounts.
There are some people who go to extreme lengths to avoid Fats and Sugars, but this is not necessary. Fats are an essential nutrient, and sugar, while not necessary, is a type of carb, and can also be consumed in a limited amount.
So if you calculate macros, fats should be included, rather than cutting them out of your diet.
I wouldn't be overly-concerned with 'fat-free' and 'sugar-free' and 'reduced fat' and all that other stuff.
If anything, a better choice is to just healthier stuff in the first place. Drink water instead of 'diet coke'. Just drink no coke at all!! for instance.