I'd like to be able to invest points in stuff like lockpicking without wasting points that could be used on perk trees that affect combat. I thought it'd be a simple console code to increase the number of unspent perks, but apparently you can only do that by manually adding each perk to the character(and can result in game corruption if done incorrectly).

Is there a simple way to add a book or something which increase your perk points with the CK?

I believe this is an SKSE function, but it's not possible with the default tools. As far as I can tell, almost everything about the actual level-up system is obscured from Papyrus.

My perks mod (ASAP) does something similar in a sense...
After you choose a class or specfic skills to monitor, you get the perks for those skills automatically when you reach the appropriate skill level.
Perk points are still awarded when you level up, so those points can be used in other perk trees.
Feel free to open it up in the CK and see how I did it. Who knows, you may come up with a better mod...

Yes I've found no way to do it in the stock game, but with SKSE you can use the Get/Set/ModPerkPoints functions from the Game.psc script. I've tried it and it works well.