Should I use 1-inch pipe for water main?
Comparing the pressure drop between 50' of 3/4" and 1" PEX...going up to 1" saves 1 psi at 5 GPM flow rate, and 5 psi at 9 GPM and 7 psi at 11 GPM (when you hit 10 feet per second in 3/4" PEX, a velocity which shouldn't be exceeded). In other words, you need to have pretty significant concurrent demands before the pressure drop in that pipe run becomes noticeable (or where pipe erosion from high velocity becomes a concern) - like filling two tubs or taking four showers at the exact same time, plus running a dishwasher or washing machine. It's possible that with so many kids that's actually a reasonable concern for you, but for the typical household there would be little benefit.