I always tend to rotate my tyres. Keeps wear even and helps with sawtooth on the rears (which was very prominent on Pirelli P7s).
Lease companies don't really care much, as if you lease over long time it usually costs them less not to pay for rotating tyres (they'd be charged by tyre fitters for this unless they got new tyres at the same time), so they just replace when needed as they don't actually need to drive the car.
I once turned up at a tyre place because I needed 4 new tyres. Leaseplan in their great wisdom opted against fitting 4 Michelin tyres and told them to put 2 Pirelli P7 on the rear and 2 Dunlop Sportmaxx RT on the front. The freaking car was undriveable (very tail happy but not in a good way) until I swapped them and put the very hard P7 on the front and very soft Sportmaxx on the rear..... but obviously they don't give a sh!t, the message I got was that Pirelli and Dunlop are their preferred (read: cheaper) brands.
Now I always phone tyre company a few days in advance to check they got 4 tyres of one of their 'preferred' brands in stock - that I am also happy with.
It is generally best to have tyres with more tread (or grip) on the back, regardless of whether it's FWD, RWD or AWD as the rear axle is what gives a car stability. This is still the case with braking, it's always better to loose grip on the front rather than the rear. The average driver can handle this easier than rear sliding about which is what usually sends you spinning.