I think there is a number of things you can do:
1. consolodate the controls in the cluster (use arrays, check boxes instead of buttons, change sizes, use clusters inside cluster, remove labels etc etc.
2. obvious: reduce number of controls. Big clusters are similar to subvi's with lots of inputs/outputs - no information hiding and little modularisation.
3. dynamically and programmatically show the control in the cluster you want to show. You can do that with the code I posted
here. You can put a "next" button next to the cluster that loops through all the controls as you push it.
good luck,
aartjan