Personally, I prefer to have both an Open and a Novice tournament on the same day, either Saturday or Sunday is fine. We have several parents in our club that will only do Saturdays tournaments for their Novice wrestlers and there have been several Saturday Novice tournaments this year to accomodate those parents. However, as the season as well into the thick of it, there are going to be fewer and fewer Novice tournaments on Saturday for these parents to take their kids to, and I have suggested to them that if they are dead set on not wrestling on Sunday, then they should start now by trying their kids in some Open tournaments to see where they are skill level-wise.
Most things that I have liked about running the Novice tournament on the same day as the Open tournaments that have been run so far this year is that they are split session, with the Novice running in the afternoon session. I think that this is a wise idea for breaking new and novice wrestling families into the sport so that they don't have to spend all their day at a wrestling tournament.