There is a long history of O-290G conversions, an internet search can bring a lot of it to you.
I have an O-290G with an O-320 crankshaft & connecting rods. Many O-290G conversions have upgrade parts, so read the engine logbook for a start. You may have a desirable crank.
I have a Ted Hendrickson prop on my T-18, and a CATTO on my RV-8, neither have metal leading edges. In rain, I slow to under 2100 RPM, which will still blast right past a spam can going full tilt.
I did run the Hendrickson full blast into the rain for 5 or 10 minutes. It did strip the urethane varnish off the blades, in a narrow band near the tip. The white painted tips were unaffected. A little touch up, and a few days to let the varnish dry, we were back in business.
Your mileage may vary, but I suggest you fly with the prop you have, avoid rain when you can, and slow to under 2200 when you must fly thru the rain.
Keep that prop sealed. if you see exposed wood fiber, put some paint or varnish on it. Wood props are great, you just need to get the right attitude and learn how to take care of it.
After you fly your current set up for a while, you will gain a feel for any upgrade. Maybe you would like some more speed or a better climb rate. Maybe your weight & balance will permit a few more pounds of prop...or not.