Let's face it - the lockpicking perk tree is not very interesting or compelling. There's basically nothing in the perk tree that demands critical investment. So here is the obvious, straightforward, so-simple-yet-so-right way to improve the lockpicking perk tree: the perks should make it just POSSIBLE to pick the lock - not easier.
A return to Fallout 3's lockpicking basically. For example - If it's an Adept lock, you need to have at least 50 in lockpicking and the "Unlock Adept locks" perk. If you try to unlock a door without having the appropriate perk, you get the message "you lack the skill to pick this lock" - just like in Fallout 3.
Think about it. It makes investing perks in lock picking actually significant and meaningful. It means new areas are available, access to unique treasure/environments/items/people etc behind locked doors, and so on. This was great in Fallout 3/New Vegas... you come upon a door with a Very Hard lock, and you are instantly curious about what wonderful item lays beyond - but you can't get to it yet... Giving you the incentive to improve your character to be able to unlock the mysterious door later.
This should return in Skyrim. Being denied access to areas unless you spend perks in Lock picking... would really make the perk tree feel actually worthwhile.
I agree in principle, but if this was in the game, then I would only be comfortable with it if the Lockpicking perk upgraded itself like the Perk-system in Oblivion. No perk tree, the skill would just unlock perks on it's own when it got to a set skill level.
Also, Bethesda needs to add in a way for Mages to pick locks, by re-adding a tiered "unlock" spell. And, they need to add something for warriors to use to pick locks as well, such as the ability to bash doors, chests, etc. with a two-handed weapon or something.
With this "bashing" ability, a warrior could "pick" locks without actually having to use lockpicks, but they would also have a high percentage chance of destroying/eliminating some items inside of a chest/strongbox/etc. This could also add in possible perks, which would decrease the % chance of your bash destroying items.