Aside from weight, is there any reason why one wouldn't use wood like cherry to build a strip kayak? I would think that cherry strip kayak properly glassed/epoxied and varnished would be just gorgeous.

There is no reason why you can not make a kayak entirely out of hardwoods and, if you're careful, the finish weight may surprise you. To compensate for the extra strength and stiffness of the hardwood you can thin down the strips to just over 1/8". It will be a more challenging project as any hardwood will be more difficult to bend and sand. Your joints will also need to be tighter as well. You probably know all this if you've worked with any hardwood.

To date I've built two kayaks entirely out of hardwoods.

The first was the "Nereida" Njord that was built in 2007/2008 for a customer in Spain. It is 80% Honduran mahogany with the remainder curly maple, black walnut and black cherry. The finish weight was only 43 lbs (19.5 kg) for a 18.34’ (599.0 cm) by 20.08” (51 cm) sea kayak.
http://clearstreamwood.com/WordPress/portfolio/kayaks/2008-nereida-njord-spain

The other one was the "Neytiri" hybrid Night Heron I built for customer in 2010. The hull was 4mm okoume. The deck was double book matched African sapele. Finished weight of 37 lbs (16.8 kg).
http://clearstreamwood.com/WordPress/portfolio/kayaks/2010_hnh