You're doing ok, actually better than most new owners, and it looks like you did some research. There are a couple things I'd recommend though.
No steak, even though it's boiled it's still a meat that is high in fat. There are some folks that will feed it as a very rare treat but not as a part of their regular daily or weekly diet plan.
The other protein, fruits n veg all look fine.
The exotic nutrition on the other hand is not that great. There are few hpw diets out there made by different companies and it can get confusing very fast. The only thing from exotic nutrition i would buy is their cages. The food and snacks are crap.
Critter Love hpw diets are the most widely used of the hpw's, it includes protein, vitamins and minerals in the staple, so you wouldn't feed any extra protein like you are now. There are recipes for salads that are fed along with the staple. All the information for the diets are on the website and you can order a sample of the diet to give it a try and see how they like it. https://www.critterlove.com/
The list of food your currently feeding is ok for a short term diet or if you run out of staple and do a junk food night. But for long term they should be on a more consistent balanced diet that provides calcium, vitamins and minerals gliders need to maintain a long healthy life.
Pellet food is a hot topic usually
some promote them in addition to their staple and fruit and veg, but not as their main meal by themselves.
Others, don't like them at all.
Personally I don't feed them, because I feel there is to much of a risk for aflatoxins if the pellets aren't stored properly. But I don't have an issue with anyone that does use them in addition to their balanced diet
If you are going to use pellets in addition to their normal food use a good quality pellet, most recommend Petpro pellets, I believe they are the same pellet Critter love sells on their site.
I hope this helps some and good job so far