To accomplish the approach it sounds like you're describing, I personally would probably use a powershell task to implement the switch statement and then a set variable task based on the powershell task output. Or maybe set the variable using a notification on the powershell task. I haven't tried that.
To accomplish the result it sounds like you're describing, I would probably have a (job) variable holding the values to loop through, one per line, and then...a Visualcron loop to run through them.
I have a suspicion that your use case is going to be more complex than I am able to gather from your description, though, in which case that loop idea might be completely unhelpful.