Thank you for your interest in several of our PSoC architectures. It is correct that PSoC 1 covers a lower price range than PSoC 3/5. Reasons are obvious. There are much more components, memory cells and programmable logic blocks on a PSoC 3/5, so the cost to produce and test the chip are higher.
concerning your question for a professional compiler; the Imagecraft compiler has seen continous improvement and the generated code with the free version is getting smaller with each published version of PSoC Designer. If your program is just "a little" too big and the time to optimize your C-program will be several days, it is much more cost effective to test and probably buy the Pro version of Imagecraft. http://www.imagecraft.com/devtools_Cypress.html
You can test the additional optimizations for 45 days and then decide whether it is worth to buy it or not. IMHO it will take just a day or two to determine how much the code will be shrinking. Improving a couple hundred bytes can the the difference to add a new function or not, using the same hardware.