Agreed, top post. Comparing Long, Tadic, etc. this season to last is ludicrous, since Mane and Pelle gone makes a huge difference to the whole team. And don't get me started on someone comparing Tadic's performances for Serbia compared to his ones for us. Completely different teammates FFS.
A quality striker will lift the whole team. If Mane and Pelle were still here, and we were getting the same results as we are this season, then it would be fair to criticise Puel. But until the club brings in the players we clearly need it's unfair to compare him (or our current players) with last year.