Does the level of a Skill matter in terms of its power? I know they enable unlocking perks, but if I'm not going to bother getting the perks in a tree, do I even bother leveling it? For example:

Do your fireballs hit for more damage with Destruction Magic at 50 instead of 45?
Does Conjure Familiar conjure a more powerful spirit wolf with Conjuring at 60 instead of 30?
Do you hit harder with level 50 One Handed Weapons over 30?

Weapons and armor become stronger, magic becomes cheaper.