Move from auto-entrepreneur to entreprise individuelle or SASU?

I have been auto-entrepreneur business in France since 2011 and I work as a freelance technical translator for translation agencies and direct clients (mostly outside of France). I now have decided to change my legal status in 2017 in order to be able to charge/pay taxe sur la valeur ajoutée (TVA)  and also to deduct my expenses (not very high) from my tax payments.

I already officially cancelled my auto-entrepreneur business for the end of 2016, and I had been thinking of changing my business to an Entreprise Individuelle, but a fellow translator recommended me to consider a SASU (société par actions simplifiée unipersonnelle) business in France instead.

So I went to see a tax advisor (expert comptable) last week and he gave me the same advice as my fellow translator, to create a SASU instead of an Entreprise Individuelle. He said that the SASU structure would be beneficial for me in the future, as I want to grow my business. For now, my CA are very modest, I will probably have around 25,000 euros CA in total in 2016.

I do plan to increase my business, but I will probably always work alone (no other employees) and I probably won’t have enormous increases even in the future in my line of business (translation).

So my question is what I should ideally do now in relation to set up a new business in France:

1. Is it really worth to move from auto-entrepreneur to SASU right now, considering that the fees for setup and for running a SASU are higher?
2. Or should I establish an Entreprise Individuelle first and see how things go?
3. Or should I maybe even consider to re-register as auto-entrepreneur as I am still below the limit of auto-entrepreneur?

My husband has quite a high income (employee) compared to me, and therefore we are taxed together once a year. We don’t have property and we don’t have taken any debt/credit that we would have to pay for. I do have a private pension plan in Germany where I pay 360 euros per month. According to the French tax authorities this money cannot be deducted from our tax payments.