Before I start: a disclaimer. My day job is at a manufacturer of such products. To avoid any potential conflict of interest or perception of bias, I wont make any specific recommendations or mention who the employer is.
Headset style and comfort is a personal thing. Consider if you want it on just one ear or both. Presuming you have a dedicated work environment without significant noise sources, the microphone isn't so critical as long as you place it well when wearing the headset. Pretty much everything comes with noise cancelling microphones anyway, which help a bit, but good placement should be the priority. Also, all else being equal, a longer boom helps.
If you want to go wireless, how long will you be working each shift? Make sure the battery is up to it, and as usual that means taking the marketing claims with a pinch of salt. Also consider that as batteries age, their life will drop. If no working headset = no work, have a backup plan ready. Even if that means plugging in your gaming headset in an emergency.
At that range I'd be a little concerned about the reliability and quality of basic Bluetooth. I'd look at DECT, high power Bluetooth, or other longer range proprietary solutions. I use a DECT headset at work myself, but I use a contact centre targeted corded headset at home for gaming communications. They are designed for full working day use, and optimised for voice quality, not music quality. The goal is to have best communication clarity, not necessarily the most natural sound.
Random: where offered a choice, ladies are more likely to pick over-the-ear types as they are less likely to mess up their hair than headband types...
