Welcome, I am glad that you have found this forum.
You are correct, it can time, more for some than others to develop a trusting relationship with a human, that is bonding.
You sound like you have done very well, and for the most part I recommend continuing an hour a day with them on you if you can. That is plenty of what I refer to as "pouch time" and leaves them with plenty time to get needed sleep.
I personally never learned to take the bite. One of my girls (from my first pair), Lulu was a very crabby girl, and would lunge at my hand, attacking and chasing it away. What I did was pull away initially, but immediately go back and keep doing so until I could touch her without being attacked by her. I felt I still won, lol.
We've come a long way with consistent pouch time, and play time. I can trim her nails easily by distracting her with meallies, and even lets me hold her in my hands during day time hours. At night time when awake, most gliders will not like to be held.
My girl Skadoosh (the other half of my first pair) was more easy going, they have totally different personalities. But they have seemed to have switched a bit also. Skadoosh is still really sweet, but less adventurous as she used to be, now Lulu is the most adventurous, opposite than it used to be, also Skadoosh seems more timid of my than Lulu, also opposite. Skadoosh used to hang out on me, coming to the front of me or sitting on my leg so I can pet her a bit during playtime, now it's Lulu that does that and Skadoosh won't so much.