I was in somewhat the same position.
What you want is a 4 blade propeller and pitch that gets close to your engines highest recommended RPM at WOT (full throttle). You can get that max value from your engine manual. I have a 4.3 Mercruiser and its Max WOT RPM is between 4400-4800RPM. The prop is a stainless solas, 4 blade, 17 Pitch and that gets me to 4600RPM. It has plenty of power for wakeboarding with 5-6 people onboard without any issues. A 5.0 should crush this :-) The 4 blade gives you more holeshot, which gets you onto plane faster which is especially necessary for towing and watersports.
If you can afford it, go for a stainless steel prop as you get more "grip" than flex in the water. If you are a novice at boating recommend sticking with Aluminum for now as stainless steel is vastly more expensive. If you hit anything on a lake etc there will be tears.
When was the engine last serviced? and any marine growth at the bottom of the boat?
Proud owner of a Maxum 1800SR year 2001.
Engine: Mercruiser 4.3 LH 1996 carb V6 engine.
Outdrive: Alpha1 Gen2 with 1.8gear
Keen interest in anything electronic or gadget related!