Explain..I see it the opposite way
Novak R1: Klizan, can play well, but is no grass specialist, is not laying well as of late, as is the biggest head case I ever seen in tennis (seriously, I watched him here at SP).
Nadal R1: Milmann, easier on paper but an Australian who can play on grass, and played a few warm up tournaments on grass. Serves big. Tinny chance for a monster upset.
But I will be nice and say Djokovic has a harder R1 (even if I do not actually think so).
Novak R2: winner of Pavlasek/Escobedo.
Nadal R2: winner of Istomin/Young, most likely Young. Young is playing quite well lately (as you noted elsewhere), can play on grass, and played a hard match against Djokovic on Eastbourne. Istomin can hit big too.
Nadal has a much, much tougher R2.
Djokovic R3: probably del Potro, maybe Kokkinakis. del Potro played zero tune ups, lost twice do Djokovic this year. Kokk surely has potential, but it is young and coming from a long injury break.
Nadal most likely R3: Kachanov, maybe Kuznetsov. Kachanov is playing really well, specially on grass (he was ripping the ball in Halle). I say he is my best pick for a surprise result this tournament. Kuznetsov is also a fine in-form young player.
Nadal has then, again, a much much tougher R3, for me the toughest R3 from all higher seeds.
Djokovic prob. opponents on R4: Lopez or Monfils. Lopez is a hard test, if he gets there, I give you that. In fact, if it wasn´t for him, Djokovic´s draw would be the easier draw of all time. Monfils is a guaranteed win for Djokovic.
Nadal probable opponents on R4: Karlovic/Muller, both tough grass courters, with recent good results on grass (and titles). Muller has upset Nadal before, and always gives him a tough match.
So even on R4. Lopez, if he gets there, can be seen as the better player, but the match up factor for Nadal, in Muller case, evens it out, to say the least. And nobody wants to face Karlovic going deep at Wimbledon.
Djokovic prob R5: Berdych, Gasquet, Thiem. Thiem is a "cow on ice". Berdych days of being dangerous seem to be over, and Gasquet could be a threat (unlikely).
Nadal prob R5: Cilic, Nishikori. Cilic plays well on grass, and is playing well lately. He is one of the best, if not the best, outside bet for the title (I mean, out of the big 4). Nishikori, if he gets there, would surely be a threat.
Nadal has then a much tougher R5.
From then on, anything could happen. I agree that Federer would be a much harder SF opponent than Murray, but if all of them make it to the semis, it is a straight fight for the title.