JC, I would start with your motor hieght. I've read and witnessed time and time again where dealers and manufacturers simply bolt up the motor with no thought in the world to what it means for boat performance. Trim the motor down so the cavitation plate is level with the boat, take a straight edge and hold it to the bottom of the boat so that it it extends out to your motor, then get a measurement of how many inches from the bottem of the boat to the center of the lower unit cone / and or prop shaft (Typically the same). A good starting point would be around 4". I've had mine all above 3" but that under ideal circumstances and with a custom prop. at 4" run it and see how it handles and where the max RPMs fall with the lightest load you'll typically run in the boat. For me, that's 2 people, emty livewell, only two seats, regular gear (I leave all my gear in all of the time), a few things in the cooler and a tank of fuel. Once you some of this info, then you can move on to finding a prop.
An Enertia or Enertia Eco would probably do well on that rig. They turn a little bit easier than the standard stainless prop so you can typically go up by 1 degree of pitch comparitively to a stainless prop and should run the same RPM as the same pitch aluminum. My only complaint is I was running a 22P Enertia which was the highest pitch they make in that prop and for what ever reason, the higher the pitch the smaller the diameter in that series. This didn't work with will a high engine hieght Where I'm surfacing my prop when trimmed out. Supposedly these work better on lower engine height settings and for those not running jack plates.
Food for thought
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FYI, hydrofoils do nothing once your up on plane, if your boat is setup right, it will be completely out of the water once up and running. They solely exist to help with bow rise and hole shot, both which I feel can be fixed with the right prop and boat setup on most rigs. A good set of electric or hydraulic trim tabs would be the best route if prop and proper setup doesn't fix planing or hole shot issues but they are significantly more dollars. Would be nice for rough water and when carrying heavy loads or offset loads also!
Shouldn't lose any speed going to a stainless prop, if you do, then you need to reassess what prop your running. Comparing different stainless props all in 21P, I witnessed a 6 mph difference at WOT between the quickest and the slowest. Not all props are created equal and all were mercury brand just different styles.
