BUT - you should be aware - there ARE reports of rear AVONS bursting. This is NOT a new thing. The number if incidents is NOT high but it's happened and is not confined to a batch of them. This is not to PANIC but simply to state the facts. It did not put me off testing them.
Much of the whole tyre thing depends a bit on the rider and where he is. If it is cold/cool where you live - I'd suggest you think about staying with ME880's.
Avons handle better - yes. But they have to be properly warmed up OR they are skippy if it's cold/cool. Do not expect them to simply grip from mile-0. And they shred just as happily if you push them.
Metzlers will even grip ice - just. But they do NOT like being pushed hard for hours on end at 35-40°C - not here in Spain anyway. They are a simple but VERY over engineered tyre.
IF - and I mean IF - you have no issue running non-standard sizes - then I'd suggest there is a mass of evidence to support the Bridgestone E-Max rear 240/55VR16 -
@1olbull has documented the restrictions for non-standard use on ABS bikes. But ime like the Avons - they need warming a bit.
There is also a Metz 145/75R17 and (in Europe anyway) also available in Z rating.