Correct! There are 4 lavs separating J and PE, 2 on each site separated by a diagonal curtain, which hints 2 of those are for PE/Y passengers (you can also see the interior is just the regular Y lav, none of the finishes is similar to that in the middle of J).
As for your seats, I think they are the best in PE, and you shouldn't worry about foot traffic, smels, noises, etc. Do try to board early as there's limited overhead space, and make sure all goes up, since you won't have anywhere to store anything during taxi/take-off/landing.