Not that we're far apart. By all means take some Chacos, maybe something like that company's Z1 ($95; www.chacousa.com). Comfortable for casual evening dining and loafing in between bouts of more strenuous activities. They'll probably also work well for your rafting ventures. For more serious footwear, at least take some solid trail runners, such as Montrail's Hardrock Trail ($90; www.montrail.com), Salomon's XA 2 Pro ($90; www.salomonsports.com), or an all-terrain shoe such as Tecnica's Vortex Mid TCY ($100; www.tecnicausa.com). And don't overlook the fact that lots of really good light hikers exist out there that are as nimble as trail runners but offer better ankle protection and support. Asolo's FSN 95 ($150; www.asolo.com) has been out for a few years now, and has been extremely popular and reliable. Boreal's Tundra ($200; www.boreal-club.com) is another excellent boot that won't slow you down.
But, you know the terrain, so use your judgment. Particularly if you don't plan to carry much of a load, then good trail runners likely will work just fine. Hope you have a good trip!
Check out more trail runners and light hikers in Outside's 2004 Buyer's Guide.