I would not use a fan on my bud as it's drying. This will open your buds instead of having them dry tighter. I would use a dehumidifier to keep the RH low and a heater if it's cold, but again a heater can dry your buds to fast.
Slower drying, better buds, more solid structure...
Faster drying (fans, heaters, sun...) you will have buds that turn into dust when crumbling with your fingers.
Take time when drying. 14 days, in darkness, with mild air circulation. Kind of if you dry it in a closet, you need 2 holes, one at the bottom for intake, and one hole at the top of closet for outlet. If too hot, put PC fan in outlet hole.
Do not use microwaves and stuff. it shrinks the bud, kills some thc. Very pointless if you spend 4 months of growing and then destroy it all by inpatience. All you need is another 14 days...
SLOW DRYING IS THE BEST.
Might you have a weblink to that amazing rack? That looks stellar!