Re: Bigger motor......more power!
The size of the motor was most likely determined by cost and what market segment Ridgid was going for. They were looking for something that can run on 115 volts and 15 amps. That is pretty much your limit. If they put a more powerful motor on they would constantly getting complaints that its tripping 15 amps or even 20 amp 115 circuits if anything else was on it. If they made it 230 volt only then a lot of potential buyer wouldn't be able to use it unless they have a 230 volt circuit available. Or they would factor in the cost to have one run.
I would guess that a 2 hp motor could be used if you had the occasional cut that would require the increase in power. But if you were constantly needing the extra power then a bigger more powerful saw would be a better investment. Constantly putting the power from a larger motor through the saw is only going to wear parts out faster and put more stress on parts then they were designed to for.