Hi SR71P38,
You've struck on the need to match up the blades and the generator.
For each part, you can make a chart to visualize what they do in different wind.
Starting with the generator, plot the point where you have the rated power and speed on a chart. The chart has speed (RPM) on the bottom, power (Watts) on the vertical side. From that point draw a straight line to the 0,0 if you are using a DC motor to be a generator and a battery as the load. That line is the generator's output power line but you need the generator's input power line. Any generator needs more power to make it turn than you can get out of it. For the sake of simplicity (a bit too much) assume the generator is 50% efficient so then draw a line that takes 2x as much power as the line you first drew. That's the input power line for your generator.
Now you need a power curve for the wind. There's a common equation for working that out, so no point in my trying to write all the greek letters and exponents here. To put that on a chart you'll want to have wind speed on the horizontal axis of the curve. The wind power curve is not a straight line, it's a "cubic curve". When you get that, you have to account for the efficiency of the rotor blades. Here, you use 50% (optimistic) and in this case you get to capture only 50% of the energy in the wind.
Now you have 2 graphs that aren't quite the same. To match them up, you can use the design TSR of the blades you've made. The red ones have a TSR of about 5, the grey ones are about TSR=2. When you look up the equation for TSR, you can take points from the generator curve and work out the wind speed that corresponds to the RPM at any point you pick. That allows you to plot the generator curve on the wind power chart.
Once you have a wind power curve and generator power curve on the same chart, you can tell if they match or not. If you do the plot for both your sets of blades, you can see which ones match better. What you have described all along is a combination of rotor that does not have enough power to drive the generator at any wind speed, except at some very strong wind speed where the two lines cross and finally the rotor can spin up the generator adequately.