Chica, I assume you are a direct drive with the Indigo. There is not much room for the small diameter to bight on and what it bites on is disturbed water flowing around the deadwood. What was the original prop and crusing RPM's before?
And what RPM's are you getting with the Indigo? The Indigo runs at a higher RPM's to get to the power ccurve of the engine. Comparing speed at a given RPM is not what to look for. What you want is around 21~2200 RPM's for fast cruise. Choosing a 2 or a 3 blade is problematic for finding a flat enough pitch and diameter (usually larger) to achieve good power RPM's.
Before changing anything be sure of the tune of the engine. With the Indigo you should get to 24~2500 RPM's if the engine is tuned properly.
Dave Neptune