Just for future receiver shopping purposes, now that your BD player will do all decoding internally, any receiver than can accept 5.1/7.1 LPCM over HDMI will do (these are traditionally positioned between receivers with mere HDMI switching, and receivers that can accept HD bitstreams). So you don't need TrueHD or DTS-HD Master Audio built-in.

Regarding your STR-DE635, it's quite an oversight that it won't let you adjust the level of the front versus the back (but will still let you do SOME stuff such as left versus right). I can't imagine any situation where this would be expected to sound right. Of course I'm a little surprised that the BD player doesn't offer it either - it's something I would really expect on any player with 5.1/7.1 analog outputs, but I see it's actually not that common.