portrait lens kit?

I occassionally take portraits of young children as a very small business venture (mainly friends and family). I have a D700 and the following lenses:

50 1.4 g
24-120 f 4.0
70-300 4.5-5.6 VR

Since I have gotten a Nikon J1 with 10-30 and 30-110 lenses for taking general everyday photos, I hardly use the D700 unless I am doing a photo session.

Thinking about selling my current lenses and getting the 50 1.8g (I understand it has faster AF speed than the 50 1.4 g which is important when photographing young children) and the 85 1.8g.

Would anybody advise against this?