Abuse local variables have brought trouble. First, for each copy of the local variable, Labview will keep a copy in the memory of its current value. It may not be a problem for a numeric but could waste a lot if the variable is an array. Second, it may bring synchronizing problem or race, if local variables being used as both read and write node. Much care has to be taken when it is changed at different places. If the variable doesn't have to be shown, why don't you just wire the datum to the next node where it is needed?
If all these being kept in mind, I think it is not too bad an idea to use indicators. Actually that are indicators built for.
