And also: Wikipedia - Bluetooth#Security
The first question then would be: did you have to enter a PIN in order to pair the Bluetooth peripheral?
If you live in a radio-busy area … consider a wired keyboard or a wired lapdock.
Bluetooth pairing may be OK if you can pair first in a radio-silent area (i.e. hundreds of metres away from anything) and the two ends will remember a link key.
Yes
Less.
One thing that I would wonder about, when you have many protocol versions and a history of plenty of security issues, is whether downgrade attacks are possible and whether you can defend against them.