If you know your way around basic gear (carabiners, rope, & prussiks), that is all you need for a pin kit in 95% of the situations.

For example, knowing how to tie a Prussik/Autoblock on command is critical, and knowing how to spot an anchor on shore quickly is also awesome. These turn out quicker rescues.

I am also a huge promoter of the Munter Hitch (aka a belay/rappel device made with 1 locking carabiner). This knowledge has proven to be more useful than the pin kit itself.

http://www.whitewaterfreestyle.com/carabiners-safety-gear-whitewater-kayaking/

-Adam Johnson