First of all I don’t like the word diet, I prefer eating plan. Diet is short term and to reach goals and maintain them you need long term.
1) Yes you can eat late night but don’t make it a habit. Have a sensible healthy light meal.
2) Control sugar intake, all added sugars are not good.
3) Fat is a necessity but the good kind is what you want, like found in nuts, seeds, fish and avocado.
4) Watch salt intake especially in soups, pasta sauces, condiments, mixes, cheeses, canned goods and even in protein like chicken(no need to add more when cooking).
5) Speaking of protein, about 20- 25% of your daily calories for a active adult is good. Some may have other opinions and the numbers may very but this is about middle ground. Try to get 20-25g post exercise.
8) Carbs are good! Again stay mostly with the good kind(fruits, vegetables, whole grains)
Do indulge once in awhile. For me the key is Moderation! Too much of one thing is not good.