DIFF idfent.
FADEC is the computer which controls the engines. Thrust manaement is controlled by the Flight Management Guidance Computer (FMGC). The slow speed protection in Normal Law is the Alpha Prot speed (a function of IAS, loading and Alpha). If you get to this point, Alpha Floor kicks in, TOGA thrust is applied (and can't be deselected without turning off the autothrust which will have automatically switched on) and the aircraft will climb like a fart in a bath assuming the autpilot is in. But this happens at a very slow speed - a speed at which a conventional aircraft will be close to stalling - and a speed at which I have never had to fly a tanker. Even refuelling Alberts!
But if it's a problem, I guess it could be changed. It is software and sortware can be re-written.
How easy would it be able to make a slow approach to the basket. Very, I would say. The Airbus thrust levers work like any other if the AT is not engaged. There is a misconception (probably because they don't move by themselves like Boeings) that there is no manual thust control. Of course there is. If you click off the AT or move the TLs out of the detents, manual thrust is what you have. And if the engine response isn't adequate, refer to my previous comment regarding software.