How to make Brie En Croute less rich/cheesy?
Use younger Brie.

You can get Brie in various ages, all the way from barely a week old - which is clean &amp; white all the way through, &amp; almost dry &amp; crumbly, mild as cream cheese [Philadelphia etc]; right up to a year or more - dark yellow &amp; pretty much a gooey liquid with a slightly more solid centre.  

Obviously, the older/more ripe, the stronger the flavour.