Now, I'm confused.

Treating your room properly with bass traps and diffusors will give you improvements greater than the equipment upgrade your contemplating IMO. It can be DIY, or with the many cost effective suppliers. You can do treatments in steps, and if your willing to go all in, the transformation will be startling.

  LP 

+1 lpretiring

Get advice from GIK Acoustics. Great products at affordable prices.

In general, you need to treat your room in the dimension you are lacking. If you need width, treat the sides. If you need depth, treat behing speaker and listener. 

There are many factors to soundstage.  A cable, speaker placement, preamp, DAC, etc.  Happy Listening.

All recordings are artificial and many (particularly multi-tracked rock and rap) are far from the "sound of musicians playing in a room"! What many prize in a stereo system as "soundstage" is often an illusion caused by wall and floor reflections! 

Anybody remember the AudioPulse reverberation device? It allowed one to dial in various settings: "small club" all the way up to "cathedral"! It contained a two-channel amp to be connected to a pair of speakers behind the listener. And it gave surprisingly good results when used judiciously! This was back in the mid-70's before HT.