Finland's oldest gaming magazine (and its predecessor) have always had an unwritten rule to never score anything 100/100 - and as far as I know, only Space Quest IV got a 99, half as a joke.
I kind of agree to that mentality, there's no perfect game, there's always something to tweak or to add.
If we're talking about nearest to perfection - instead of just best games that above 9.5 round up to 10 - strategy games are a genre where you can get close. Populous, Master of Orion 1&2 and personal favorite Crush! Deluxe come to mind.
Also some freelancer games like old Pirates! and Privateer 2 are among top ones.
Straight up best game series are Wing Commander, Phantasy Star and Monkey Island.