I think Mac would fail both of these- it isn’t disease resistant and it isn’t all that sweet.
Fuji is sweet, but not disease resistant. It also can take a while to bear, as my dad has a 7-8 year old Fuji which has just had the first flowers last year, but still hasn’t set a single apple.
I’d suggest Sansa- it is a sweet summer apple (more sugar than most other apples in that timeframe, along with Zestar) which also has some disease resistance (not fully scab immune, but moderately resistant).
If you want sweet, with a bit more flavor (not acid like a Johnathon), I second Dave’s suggestion of Golden Russet. Kidds Orange Red is also very good.
Everyone has different objectives, and it sounds like the OP wants something known and disease resistant. Because my garden is limited, I did the opposite and tried to get everything highly rated I COULDNT find as a Publix or Safeway. So this year I’m grafting Arkansas Black, Golden Russet, Belle du Boskoop, chestnut crab, and a dozen others onto rootstocks, and they will slowly be brought back together as 1-3 frankentrees and a couple others left to a greenway near home as “field apples”…but I get what the OP is shooting for…
liberty does seem to get mixed reviews, and if you (the OP) are already grafting anyway, have you considered multi-grafting? It gives you more latitude on pollination times, and also on ripening times. Plan it right and you can have newly ripening apples for at least three months