I moved this over to give a little more writing space.
Can't say I agree with many of your points.
I don't see how your proposed friction load will let you measure torque which is necessary to measure rotor power. Also, you don't want to start a test run with the load on, it'll never start. You want to be able to smoothly adjust the load from zero to max while it's turning.
"Since I already have my rotors and magnets however, I am committed to a certain size motor, around 3-7k depending on how I wind my stator. So that is why I wanted to know the torque this particular load range puts out."
Okay, so you want to design a rotor to match your partial alternator, basically, magnet power. Torque in ft-lb = (Pkw x 3918)/RPM. This would be for the INPUT power to the alternator. To get the input power required, you need to know something about the alternator efficiency at a given output power. This means that you essentially have to do a complete alternator design first, because its efficiency is a big variable depending on many things. You might want to read Flux' treatise again. You may have put the cart before the horse by machining your rotors first. THINK SYSTEM DESIGN!
"If I knew how much torque 7KW put on the shaft, I could design a rotor that would be sure to start below the cut in(60 RPM) and perhaps reach MAX RPM in the fastest time."
With an axial flux alternator, start-up is not an issue. Almost any rotor will start okay. Other than bearing and seal friction and inertia, there is no load on the rotor at start-up. The electrical load won't begin to be applied until you reach cut-in RPM and even at that, it'll be small. This is why I have trouble seeing your interest in acceleration. It doesn't seem to tell you much. What you really want to know is the rotor efficiency in the wind speed range that produces useful power. By the way, how did you determine the 60 RPM cut-in?
"RPM above the MAX would be wasted, since you would be shutting down when you reached MAX AMPS. So designing a rotor to get there the quickest would be a direct result of better lift and take in those short bursts of wind that seem to happen more so than a steady flow of wind."
There are two schools of thought on rotor acceleration beyond cut-in speed. Using rotor weight as an example, since weight determines inertia, which also effects acceleration, and comparing two rotors, one weighing twice the other. One school says, as you do, that the lighter rotor, which accelerates more quickly, will take more advantage of additional power in the gusts compared to the heavier one. The other school says that the heavier rotor will store more energy in the flywheel effect and release that energy during the short lulls of the wind. I think it's probably a wash with neither having much advantage in total energy harvest.
Another point about an acceleration measurement in model rotor testing, is how do you apply a variable load to the rotor, as it accelerates, to simulate the variable load of an alternator? The alternator load is not a constant.
"You could even play around with the root AOA to help get more torque."
"Some have stated that they feel this is the area to improve anyways, and I tend to agree, it sounds like the most logical place for improvement."
Boy, I have to strongly disagree on this point. The first 20% of a blades radius (starting at the center of rotation) only contributes about 4% of the power out of a rotor. In fact, I wouldn't even put an airfoil on that first 20% and instead, design it for the structural needs of the blade and fastening to the hub. On my 16' rotor the airfoil starts at 25% radius with no start-up issues and an efficiency of 42%. There may be sone advantage to more root if you have a high starting load such as a badly cogging motor conversion. For axial flux machines, I don't see it.
Oh, forget what I said about scale air velocity. It's wrong for a rotor but right for a wing.
Are we moving forward of backwards?
