Ready-to-use Wordpress sites: what to focus on

[AndrewC]

I am interested in working creating websites ready-to-use based on Wordpress. Would you say that focusing only on developing WP themes would be too narrow? What other services would be worthwhile offering, related to the main concept (ready-to-use sites), in terms of $$ and volume of demand?
Cheers

[Diarmuid]

How about a ready-to-use ecommerce site using something like shopperpress?