@Albert Margarit (NS Eng Lead) Definitely waiting for the open source stuff.
Why use the .clicache at all? Why not a system level encrypted storage like keychain on mac? You can definitely access this in webstorm. (Im not sure what all is stored in this cache though but for user/pass .. thats what its for). You can use a key/value pair based on the accountID and store all the user/passes encrypted and switch based on the account.
For each SDF being its own project, won't this fail if you have quite a few of the same script types on a record? For me, it doesn't seem like SDF is what you should use if you are doing small customizations here and there for people.