Tory- when Natalie was teeny and we were just starting with cloth we had BGv2 and found that if we put a hemp insert inside instead of the mf one (this was before the newborn insert days!) then they fit better. I used the Ella's house ones I think (long and thin?) She was really really skinny, and at 9 weeks was still only about 8lbs and the BGs worked for us this way until she was about 5 months old when I could start putting the bigger inserts in!
I find the Easyfit squishes better than the BG v3/4 between the legs, so you'd probably get a better fit, but I have yet to try them both on a teeny!