Meece, I have loaded hundreds of 3/4oz loads in 12g. And 7/8oz. Plenty good to be honest.
However, I don't fuss over the square load thing. In saying that I don't advocate more is better. There is only so much one can do without drastic diminishing returns.
The main reason for the heavy shot load in this 410 is that it makes it subsonic.
I also do a load of 1/4oz for the garden on green dot.
#7 is also a favourite of mine also. You don't need a large pellet to break birds necks and heads! #7 is very good in my cylinder muzzleloaders too.