... "beyond the touristy stuff"
In my long-term and jaded opinion, no, not really. Even the real tourist stuff is not that much of a draw.
Roatan is a dive destination and there is no straight faced way to claim much else. The Black Pearl Golf Course seems to be a big draw, uncertain as to comparative quality, but there is the big enchilada.
Jungle canopy slides, horseback rides, some shopping (mostly for Guatemalan stuff), a miniature golf course (drinking is recommended), a Casino (a dark room with 6 slot machines), Two (2) Bojangles Chicken outlets, a Harley Davidson T-Shirt Shop, and some other stuff.
The huge draw for non-dive activities is the bar scene and restaurant availability of West End. There's the beach.
You can go to a few different charitable operations, but they are not really set-up as a tour destination. Consider
Roatan Childrens Home | Majken Broby Childrens Home, Roatan Orphanage or
Clinica Esperanza | Roatan, Honduras where you could leave $200 behind after a visit. That would be appreciated.
"Locals"? Take your pick:
Most visitors see these to be the inhabitants of West End/West Bay. In reality, there are a few different groups of "locals". First, of course, we see the ex-pat Americans and Europeans in the tourist industry. The land on the island is largely owned by the cousins of the people you will have met in Cayman. Another group is the descendants of the freed black slave sugar plantations from the Eastern Caribbean, usually referred to as Garifuna. Then there are "Spaniards", those who have come from the mainland and are very big part of the service industry. It is traditionally an English speaking island with former strong roots to the Crown, now being run by a Spanish speaking mainland government.
The only waterfall accessible to tourists in the Bay Islands is on the main island of Guanaja. As far as really cool stuff to see on Roatan in terms of physical geography it's pretty well limited to Alligator Nose, a promontory on the Northern Coast (Central zone). Worth the trip? Dubious. It is the most spectacular natural beach on the island.
Otherwise, getting on towards the East end, there are water taxi mangrove tours through the Southern side's intercoastal.
Roatan is for SCUBA. Unfortunately, most visitors that frame themselves as hard-core divers only see a small segment of the widely varied underwater terrain and geography. The North/West and the South are hugely different environments and have to "be seen" with different observational skills and dive styles.
