Hi Shawn,
Thanks for the feedback and clarification. Could we ask where you are located, and what are the speakers you have and their rough dimensions? If the Expedit 4 x 4 is 58 inches tall, then I'm assuming your speakers are roughly 32-34 inches tall x about 8-10 inches wide, and because they're up against the wall, say around 9-10 inches deep?
The placement against the wall and up against the expedit sides will block some of the center radiation and can really muck up the soundstage, plus the speakers may need to be tilted back or actually put up on stands to get the tweeters to sitting ear level. With the speakers pulled out a bit wider and toed-in, you can get some of that back, especially if you pull the speakers out to be front face even with the front of the Expedit.
At the risk of pushing the limits, you may wish to consider a more complete speaker that will still, in general, meet your visual needs, while giving you a really big boost in sound quality. You may need to upgrade your amplification as these are 4 ohms speakers though (check that your Yamaha receiver can push these, as they do like power).
The speakers that I'm suggesting would be the KEF 104/2. They have similar physical specifications (35.5 x 11 x 16.5 inches) but are deep enough so that even against the wall, they are almost flush with the front of the Expedit (Depth: 15 3/8 "). They come in a variety of finishes including black, teak, walnut, and rosewood, and they physically resemble your current speakers, perhaps on a bit of steroids! The grille even covers the bass port.
However, when properly resurrounded and center donuted (total of 4 each for the pair), tweeters checked and sorted out (drying ferrofluid, easily cleaned and re-fluided), and the crossover recapped), they will hold their own with almost anything out there, have excellent full range sound and image extremely well. Used models typically run $300-500, and hopefully local to you. Refurbishing can run about <$200, depending on you to do some of the work. There are a number of threads on AK about their refurbishment. They don't need stands as they were designed to work on the floor and sound axis tilts upward by design.
http://kef.com/html/en/explore/about_kef/museum/1980s/reference_series_104_2/index.html
http://kef.com/uploads/files/en/museum_pdf/80s/Reference_Series_Model_104_2_r.pdf
Here's some pics from the web:
See this page for some gorgeous Santos Rosewood Raymond Cooke Special Editions:
http://www.avforums.com/threads/kef-104-2-raymond-cooke-special-edition.1846348/