+1 on the Nexen Roadian, have some HP's fitted to the RR, (20"s, got them fitted £100 a corner, V cheap for 20"s! )
They are a budget tyre but very quiet, great grip, done 7.5k miles and hasn't touched the tread.
Highly recommend!
16 inch rims are the best, having rubber bands for tyres is not that good for comfort.
If those W/Ts with a less chunky tread than the A/Ts wear anything like the A/Ts, then you should be quite pleased with how long they last. I've had my D2 just over 12 months now and I'm still on the A/Ts it came with despite enjoying several green laning outings and covering about 12k miles (still have tread higher than the wear indicators!)
I'd consider anything less than about 35,000 miles to be too fast wearing!
I've been on Michelin latitude cross since December, no problems and great on the road.