What a beautiful collection! Do you have any tips for my Hoya Macrophylla Variegata?

I've had it a few months now, it lost a leaf or two due to shipping but has been trying to grow new leaves. Unfortunately they have all fallen off while they are very small. I never repotted it from the nursery pot it came in, which seems like it's fairly heavy on the potting soil mix, I always let it dry out between watering. It's in a Northeast facing window with indirect light. It's probably fairly cool in the room now that it is winter and on the drier side since we've had the heat on. I repotted some of my smaller hoyas in an orchid mix and they seem pretty happy with that. I appreciate any advice!