By parallel he ment taking advantage of multi-core systems and scales well to the some point, ie. up to 2 socket 32 core system (64 threads via HT). From what i understand core is not desiged to take any big advantage of parallel thread execuion on multi-core systems. All that work is handled via .net's infrastructure and OS's scheduler ( which is why u dont see a %100 core usage on task manager). If the core of system can be built multi-core aware / better thread distribution it will help speed of generator nicely.
By the way, somehow GPU acceleration will probably make the product one of its kind. I don't think there are many commerical product that can accelerate calculations via GPU (i dont know any actually). Even Metatrader 5's strategy tester cant get any use of OpenCL. They made distributed / network shared computation infrastructure for CPU only.
I still dont have any idea about price of Pro version, but it will worth too much a well developed GPU acceleration can be included somehow. Even in a structure of Plugin, which can be sold later/seperate.
Edit : You can also use EC2's compute nodes but they will probably cost you a fortune. Unless you use only small amount of time per day, say up to 4 hours or so, buying a new computer will be more benefical.
For big compute nodes on EC2, say C3.8x large which is 32 core, you probably need to lunch at least 25-30 instance of FSB to get full CPU occupancy. Setting up 25-30 insstance of FSB for generating a strategy is a bit time consuming for now. Better multi-core using version of course will suit better. I tried FSB Pro on Windows Azure and it was not calculating fast. Even if i manually distribute core affinity.
For the last, multi GPU / network / distributed computing support will make the product worth of... I dont know more than 1000$??