Robert, the system you described will sound great, and due to the sub will have similar impact to large speakers. Both you and your wife will be happy.
Re color, I've had cherry and currently have black. In my HT, cherry matched the dark maroon walls a little better, but I had several other black components, so the overall effect of black speakers was more harmonious.
With yellowish walls, I'd at least consider Mansfield Beech. OTOH your sub will be black. However it's often positioned in a corner, or can be hidden behind a sofa, or large potted plant, etc. Main and surround speakers will be in the open.
Also check on the grill cloth color. It's black for cherry and black speakers; don't remember about beech.
Contact Axiom -- they can probably send you representative color chips to better visualize it.
You'll likely be happy either way, but I'd suggest taking a little more time, contact Axiom, and be sure about the color. You'll be looking at them a long time.
