The Federer comparisons don't do anything good for Dimitrov, IMO. They only create unrealistic expectations.
I like Dimitrov and think he's got the talent to be a future slam winner. And, it is true that his style is reminiscent of Federer, but he's his own player. The guy has risen in the rankings every year, and now at the age of 21 he's reached a career high of 34 and likely to keep going up as the season progresses. Yet, because he was compared to Federer as a teen, his career to date is viewed as a disappointment. The days of Becker winning Wimbledon at 17(?) are likely gone. It's a mans game for sure nowadays. I'd say Dimitrov is right on schedule. He just needs to keep improving and work on being consistent day in and day out.