I personally feel a bit guilty reclining in either cabin.
Reclining a WT+ seat really does impact your space, and increases the difficulty of getting out of a window seat.

Sleep wise, don't think I've ever really slept in either cabin. Getting better with flat beds, but in a seat, my backside gets sore and I'm always figetting or sliding to the very edge of the seat to minimise contact.

Legroom doesn't make too much difference. 5ft7 or thereabouts, so my knees don't generally get crushed against the seat in front.
Not keen on any of the extendable legrests. They just don't feel natural to me when sitting.

The solid bits between the seats aren't great in WT+.
At least in some Y cabins, you can raise the armrests if you've a free seat to spread into.

That said, I've survived everything up to 13-14hr flights in economy and WT+, and my pocket has benefitted.
Not done the 787 in Y yet though (at least long haul).

IF the price is right, the extra Avios and TPs are why I would fly WT+ over Y (say LHR-LAX for £750 in WT+ Vs. £470 in Y).
A very slim chance of being upgraded is a sort of bonus, and an easy way of upgrading with Avios on occasion.

Food and service definitely aren't a reason to fly one over the other.