I suggest you either look into it in a lot more detail for yourself, or you get professional advice eg a Skype consultancy with Catharine Skype Consultancy Services or advice from Valérie http://www.startbusinessinfrance.com/ or go to another of the many sources of advice available.
Choosing the most suitable business structure can make all the difference to the success or otherwise of your business so it really is worth going to a bit of trouble to understand how the various structures work and make a good decision. What works for other builders might or might not work for you, it’s impossible to advise without knowing anything about your business model. Have you done a business plan and worked out some projected figures? You say “builder” so to start with, which trade will you register for, will it be just one trade or several, if several how many exactly? Which specific trades you register for will determine what professional insurances (if any) you will be obliged to take out, then you will be able to get an idea of how much you’ll be paying per year in insurance. This is an important factor because on micro your deductions are based on turnover, so the higher your expenses and overheads, the less attractive micro becomes. On other regimes your deductions are based on actual profits, which involves more paperwork and could even be to your disadvantage if you have exceptionally low outgoings, but will be beneficial if you have high outgoings.
So for instance if you’re going to register for 3 or 4 trades and pay out several thousand € in insurance over the year, and if your work will involve buying lots of materials and/or investing heavily in equipment, and if your wife will work in the business with you, micro would be a crazy choice. On the other hand if you’re going to register for one trade and do small jobs that don’t need decennale cover and don’t involve supplying materials, it might be a good option.