Klahne,
You are correct in what you read about ImagePrint not accepting Epson profiles; they are rather proprietary and while custom profiles can me made, it is not simple and I believe you need certain info from IP.
Nonetheless, you could try a curves adjustment layer and lightening the image or you could dial back the ink density in Epson's print dialogue: Print Settings from CS, then Paper Configuration in the driver.
Hope this helps,
Ed