Specialized Sectuer for Gravel?

Hi all, first post here. I've been singletrack mountain biking for a about a year and got a itch for a road bike. I find myself riding more of the dirt/gravel roads in the area than I do the paved. I'd like to make some upgrades for gravel riding if the bike is suitable to do so. I been lucky so far with no flats but think tires would be the first change, I have 23mm tires now, what would be a good upgrade? I know I'm limited with brake type.
Any thought or suggestions would greatly be appreciated. thanks Craig

The Sectuer is history, phased out by the gravel-worthy Diverge.

According to this http://forums.roadbikereview.com/specialized/wide-tires-secteur-265233.html 28-30c is the biggest that will fit (2011 model) so a bit thin if you'll be more on gravel than pavement.

Are you looking to buy a Sectuer or put larger tires on one?

I have a  Sectuer, looking at larger tires and any other upgrades for gravel riding.

The tires on the upper end Diverge's are classified as endurance but are pretty durable. Not so good in mud but good everywhere else. They're 30/32s and may fit.