So far I have run 3 new circuits from the breaker box on one side of the
house to the workshop and garage on the other. I have to run a 4th.

What hole size is recommended for 10/2 in floor joists? I alway drill the
smallest possible hole to minimize weakening the joists and then pulling the
cable is an ordeal.
Is it necessary to keep the holes any distance from existing holes, or am I
making too much out of this?