French-speaking is already a niche, but perhaps you want to go further into a specialist market.
There are several ways through which traffic comes (you can divide it into SE, direct, and links as Google Analytics does). For each area, there are many ways in which you can take action to increase traffic.
For starters, I would focus on SE friendly content and links with complimentary sites (eg. exchange links with romantic restaurants, flower shows, etc). This will help establish a base with SEs. Good luck!