I would skip both mesquite and hickory and go for something milder and sweeter. I have had great success with both maple and pecan. On my first brisket I ignored a lot of advice to the contrary and went for mesquite. Mistake, it is way too strong. Unfortunately the only place I can find woods other than oak, hickory, or mesquite is at a specialty barbecue place such as BBQs Galore, but if there is one in your area it is worth the trouble.