I really think there could be some big potential in a strategy creation mode that combines the strengths of the custom builder and generator: you define everything as in the regular generator but also add one or two entry/exit rules as in the custom builder or editor before generation has begun as the bare bones of the strategy. Then all strategies tested during generation would have those rules you added as well as those the generator had added.
We’ve had the idea of combining the builder and generator into one for quite some time. No promises as the future is not clear what with the scripting language and all. We do agree it is a great idea, though!