Re: Here we go...Haren
In terms of slugging, think of this way.
300's: Mostly singles, few XHB
400's: Mostly singles and doubles, few HR
500's: Good mix of hits, with lots of either HR or 2B/3B.
600's: Lots of homers and doubles/triples
I think Votto's peak is going to look an awful lot like Sean Casey's with a touch less BA and a touch more power.
Casey had the following seasons:
Age 24, 1999: .332/.399/.539 -- 594 AB, 42 2B, 25 HR
Age 25, 2000: .315/.385/.517 -- 480 AB, 33 2B, 20 HR
Age 29, 2004: .324/.381/.534 -- 571 AB, 44 2B, 24 HR
I think a line like .290/.370/.520 is fully reasonable for Votto, if not next year, then soon. You don't have to be a "slugger" to slug .500. 40 2B and 20 HR will put you over the 500 mark.
Games are won on run differential -- scoring more than your opponent. Runs are runs, scored or prevented they all count the same. Worry about scoring more and allowing fewer, not which positions contribute to which side of the equation or how "consistent" you are at your current level of performance.