My gliders don't seem to like sweets that much either. When I was feeding fruits and veggies at the beginning, they wouldn't eat much, I served it all mixed up. Then I started separating it, one plate would have only fruits and another only veggies, and noticed that they will eat mainly the veggies. And after my male, Loki, gained more weight than he should have, I started feeding fruits more sparingly (every other day, or every 2 days) and they actually seem to like that better, they still don't eat as much when I serve fruits.
In any case, I don't know if my gliders are weird or whatnot, but they don't like yogurt drops of any flavor. Instead I feed as treat Greek yogurt, they only like the honey one, they get mealies (live ones, they don't like them dried or canned), they adore sunflower seeds, and in rare occasions pistachios. But what they like the most is corn night, once or twice a month a would give them a third of a corn cob (hang in their cage, mine only like it boiled) and the next morning only the cob is left.
Just some suggestions if you would like to try them.