Not exactly what you are searching, but you should have a look at "The Reaper 1.32 (by Akua)". It is a program that allows you to adjust the heap expansion for any application quickly. Just dragging a program to this control panel, and adjust if you like to increase the heap of memory usage for this program in percentages or absolute values. The nice thing is, it is just using this extra memory when needed and possible, so you can keep the usual values, but allow a application to allocate more memory when needed (for huge documents for example).