I wouldn´t say Federer and Djokovic are neither a good nor a bad match-up for each other. More often than not both play very good tennis and it´s just a small difference between winner and loser.
Isner´s kick serve troubles Djokovic but IW 2012 and Cincinatti 2013 weren´t the most important tournaments to Djokovic.
I´d say Murray maybe, he really annoyed Djokovic with his game at US Open 2012 and Wimbledon 2013 especially.
Has to be Federer.
Similar losing H2H with both Nadal and Federer, but Nadal is a vastly greater player than Roger so Federer must be the worse match up for him