They need to simplify it. As with any power play that is strugging.
Three basic or most common ways to score on the PP(Not the only 3)
1. Defencemen shooting from point it goes straight in, deflection, or rebound and score
2. pass across the goal mouth shoot and score
3. Passing it to a player in the hash marks and one timing
You see the sabres doing number 3 the most and it is not working, also if the player misses the net it goes around the boards and out.
Number 2 was Drury and Briere bread and butter, sabres try now to very little success
Given the state of the PP number 1 seems like the best option but the defence refuses to one time the puck when they get the pass. When they do try they take to long to shoot or float it in and it gets blocked.
Just my opinion and what I see. Every coach, commentator and player will say when you are struggling, simplify, shoot, shoot and keep shooting.
The sabres? Pass, pass and keep passing.