I think it depends on a number of factors, but in general, the more exposure to the language you can have the better. I'm taking 2 sessions a week with a tutor and find that it's works out well. It gives me a few days in between to do some independent study and try to absorb anything new from the last session. However, if money and time were no object, I would probably have a session every day. I'm currently focused on speaking and listening so our sessions are almost entirely just chatting. If I could do this every day I think it would be great. However, if I was trying to learn new grammar, lots of new vocabulary, etc every day that would be too much for me.

If you have the money and the time, try taking a few extra sessions a week and see if that is too much for you or if it helps. I think that is the only way you will really find out.

Good luck!