Regarding loo's, if you take current A350-1000 configs (e.g. QR, CX), one could assume that there will be 2x loos forward of F (i.e. just behind L1/R1) and 2x loos between the two J cabins (i.e. around the galley and L2/R2) noting that QR only has one loo at this second position.
Now, it's...