How if your characters get high level the game effectively breaks and you either need to shoot basic TNs to the moon or the game rapidly turns into "I say what I want to do and I win unless I snake eye. If I do I'll spend a point of edge."
I think it's a matter of perspective.
At skill level 3 your players are the battle tech equivalent of green. Gunnery 5.
At skill level 4 they are regular pilots. Gunnery 4.
At skill level 5 they are veteran pilots. Gunnery 3.
At skill level 6 they are elite pilots. Gunnery 2.
At skill level 7 there isn't even a rank for them. They are better than elite forces. Gunnery 1.
At skill level 8 they are legends. Gunnery 0. The bounty hunter. Khans of the clans.
At skill level 9 they are better than most Khans. -1 gunnery.
At skill level 10 they are Alaric Wolf. Maybe. Because... -2 gunnery.
Skill level 10 plus a bonus link attribute of 7 or more. -3 gunnery.
Skill level 10 plus two bonus link attributes. -4 gunnery. Most likely where Kai Allard Liao is.
With exceptional attribute. -5
With two exceptional attributes. -6 only clan warriors with two exceptional attributes could get here.
That's not including special abilities.
But by rank 9 you are already the guy they call to make a shot against a moving aerospace fighter... from the hull of a moving dropship. While re-entering the atmosphere.... while inverted.