I just replaced my Oak tiller with black locust and am very happy with it. I can't see why black locust isn't used more often, it is strong, durable, good looking and alot cheaper than "exotic" woods....maybe that's it, it's not exotic. My cap rail is a dark mahogany. If you want something that looks sort of like teak but is alot less expensive Silver Bali would work (just be careful because it can check, you can tell right of it is going to though). It is often called "poor man's teak" and is being used as an alternate for teak decks. I recently built a boom gallows, winch mounts, compass mount/bridge deck,companionway doors, mid-ship hatch and combing for deck hatch using 2" Silver Bali. When fresh the color looks like Balsa, when varnished and exposed to the sun it darkens up nicely. It's a hard wood, easy to work with chisels, planes, spoke shaves or router.I have worked extensively with the wood myself and am sitting here looking at the schooner Martha which was decked with it. Here is a discussion about it on the wooden boat forum. Silver Bali Wood
NOTE:There is a hard (used for boat building) and soft silverbali
I personally really like the wood, it is supposed to have most of the characteristics of teak as far as strength, durability and rot resistance. Three of the qualities of teak it lacks, it's not as heavy, expensive and the lower silica content doesn't dull tools as fast (which makes it easyer to work with).