Rudder Size

"I know I had fear of what could happen at speed with that much turning power but it act like a brake if you go hard over"

Most rudders work as a brake after 35deg , and most are built with stops not to go over that range.

All rudders produce drag at all angles of deflection. With my large rudder I can turn 90 degrees into a slip from the fairway (unless it's really narrow) right into the slip and the rudder drag is not an issue .. or even detectable "seat of the pants".

If your rudder is too small it will be much less effective at all angles of deflection and it will take less deflection to stall or develop too much turbulence on it's backside to be very effective. At very slow speeds like 3 knots and w a really big rudder ... rudder effectiveness may be very usable almost to 90 degrees.

Basically the 35 degree rule is for faster boats w smaller rudders for good high speed performance. And the rule applies fully there.

Get rid of all that crap fouling your prop and shaft and you will probably be equally amazed at the increase in performance.

Yes the prop had a little bit of grass on it from the last time out. I just hadn't cleaned it off from the last outing when I took the pic. I always make sure the running gear is clean before we leave the dock.