Although Sneak Attack doesn't work with bows, it's still worth the pick against a boss monster for the initial strike when combined with Stealth/Stealth Potion, since it's a nice starter damage before you dodge back and using your bow to safely hitting the boss until it's demise (This also works multiple time, just wait for your Stealth skill/potion cooldown is done, you can do it again).
What skill that does work with Bow is another critical booster called "Massive Critical", which you can learn at the Warrior's Guild in New Garand, this skill can multiple your critical damage up to 300% (more or less, can't have the time to recheck it
) and insta-kill most enemies. So as a fellow bow Rogue playstyle, I highly suggest you pick this skill above all else.
Good luck with your current build, can't wait to see your progressions