With a fixed pitch prop you have to decide what you want most, good field performance, good climb rate, speed at 2000', speed at 10,000', something else? You can't have everything. Some props will be pretty good in most areas but there will always be someone who is faster, takes off shorter, climbs faster than you if you have a "generally good" compromise prop.
If you get a prop with more pitch then your take-off roll will increase and your climb rate will decrease. You may be able to tolerate that but look into all of the implications to changing the pitch of your prop before ordering. Also note that all prop manufacturers measure pitch differently, and the diameter of your prop has as much effect as the pitch. If you have an 80 inch pitch prop from Mr Catto who knows what you might need from another maker.
As you climb your engine makes less power. You must open the throttle, and turn more rpm, to make the same cruise power. It is unlikely you were getting 62% power at 2450rpm at 9500ft. Take a look at the performance chart for your engine, I would guess you were closer to 50% power.
If you have a prop that gives good take-off & climb performance you may well be able to turn it at over 2700 rpm at full throttle at altitude. It depends what your prop was built to do, and also how you want to operate your engine. There is no right answer here just a spectrum of choices. I would pick a cruise speed and open the throttle until I get it. Then adjust the mixture to minimise fuel flow - I would second the comment about reviewing how the red knob works, 50F rop is not a great place to operate. If the engine is turning too fast for your liking then you may need a new prop, or throttle back some and accept a slower cruise (burning less fuel).
Its all a compromise, just decide what you want the most. I found Sensenich metal props are the best compromise for good all-around performance, but I fly mainly below 5000'.
Pete