For the first question, you probably should create a seperate subVI for each indicator.
About (2). There are many ways to stop the loops in the subVIs (You seem to use a global variable). You could just use the numeric itself and test for a value that never can occur during normal runs (e.g. NaN, -Inf, or Inf, etc.), then, when you stop the main VI just write these to all the indicators and everything else will stop. (This can be useful during development. Once this VI is deployed in a production environment, stopping is probably not needed, just a sane shutdown of the entire application.)
