Longer balance or lighter spring

I have a Milestone 1000 SH window that is 53X63. The window is very difficult to close completely. It gets very tight and requires a bit of force to shut fully. What ends up happening is that the smaller people in the house end of latching it when it is not fully closed and close the latch on snap in window glazing breaking it. The window sill is clean and I do not see any frame damage.

I measured the balance at 29 inches and the spring is 2860(32-35 pounds). To help the window close correctly could I use a Balance that was 1 inch longer or the 2850 Balance that has the lighter spring?

Thank you,