My top three based on name quality and potential markets are:
DietRewards.com - very brandable name and sounds nice, could refer to information on losing weight or just eating a proper diet. You just have to come up with an 'angle' for the rewards part. Inferring that you could get 'rewards' for dieting would encourage people to visit the site.
Garden.pro - huge baby boomer population (now 40 to 60 yrs old) will continue to drive the gardening market. The extension suits the nice generic word for someone who wants to garden like a pro. You could also add a forum, people who garden love to talk about it.
Wedding.pro - the wedding market is always lucrative, from planning, to attire, food, cake, speeches, wine, arrangements, etc. Again, the extension suits a professional wedding planner site.
The .pro extension isn't wildely known but since it suits your words you should go with at least one site in .pro. All it will take is for someone to develop a popular .pro site and the extension will become more well known. Good luck, I too have a wide range of sites that each get little attention, to really focus on a couple would be nice.