Hi X. What do you feel your system is lacking in the first place as far as performance goes? I believe you really want to put as little responsibility on the salesman to help you decide which component should be upgraded next. I think the best thing to help you decide will be (in a rhyming fashion) "your ears and your gear". Unless you have something that really needs to be upgraded because of it's obvious performance shortcomings, I would really let my ears decide what piece I want to upgrade and then have the dealer help me by showing me different models of what I'm looking for. Your goal as a consumer is to educate yourself to the point that you basically turn the salesman into a showman. As you already know, there are tons of forums that will educate you and people who'll give you opinions on the net so your dealer is but one opinion who may or maynot have a stake in your sale but on line is where you'll find numerous but for the most part, honest opinions on gear. So tonight, listen to your gear. Is it really a cable change that's driving you to want to upgrade instead of that intergrated or CD player? How about some room treatment? Speaker placement maybe? Trust your ears and your gear!!
Good Luck
Good Luck