Slow is good. Too slow is a problem.
A closet is fine if it has some sort of exhaust of stale air. A dark, cool room will be the best. A circulation fan of some sort but not dirctly facing the drying buds. if you can control humidity i'd shoot for 55-65%. this will depend a bit on your temperature and how many days you want it to take for the average buds to dry
There is variance based on density of buds, whether you trim or not, or whether you hang the entire plant etc... Think of each variation as a tool to control how long the drying process takes. If you are in a wet/humid region, you probably don't want to hang the entire plant, for example. you do what works out best for your context.
I'm content with a 9-day drying time, on average. Some shoot for longer. I gow in the winter, so the temp is a consistent 68-70F and i run a humidifier set at 60% RH. I rely on the humdifier fan moving air around "enough." I also half-ass trim and chop it down to individual nugs that are placed in a single layer on 36" mesh racks. --- Just to give a point of reference for drying times.
Based on how your context plays out, you can adjust in a half-informed way until you gain some familiarity. If it dries too fast, try 'one' thing at a time until it's the length you want.
The other tip -- once it feels dry on outside, wait an additional 12-24 hours before putting in a sealed container -- preferably with a boveda 2-way humidipack. (58% and 62% options are good). do not buy integra boost 2-way packs. they suck and don't hold the RH anywhere near stated values. Boveda packs are within 1% and consistent.