The issue isn't how HIGH the stall can be with a particular cam --- people setting the stall too LOW for a particular cam is usually the problem. Also how you're using the car is a significant issue.
If an E might go in later, size the stall for the E. The stock cam will be just fine with a higher than stock stall. And if you're trying to optimize your acceleration times, I wouldn't go any lower than 2500-3000 for the E. If you cruise in the car or use it significantly on the street, there are some things to consider. If your stall speed is above your highway or cruising rpms (a 3000 will be), it means you'll be running with some constant slip in the converter which = heat --- so an aftermarket tranny cooler is probably a good idea.
My suggestion? Lose the automatic and stick a manual in there.
Give www.edgeracingconverters.com a good look. I and a bunch of others on here have them and they work great and their customer service is fantastic. I'd seriously look into a 3000 9.5" stall. Gets into the revs quicker due to its smaller diameter and lighter weight.
A good trans cooler is ALWAYS a good idea with an aod. Heat of any kind will shorten their life.