Two surprising things I found that improved my imaging and staging...

Congratulations. Speaker placement is a big deal and getting it right is really rewarding. Depending on the room and speakers 1/8th inch change can make a big difference. Glad it is going well!

Totally agree with you since I just did the same thing. I've been rearranging some furniture in my room to make room for a vintage system. My Dynaudio Special 40s in my main system were a little too close and not angled correctly. Once I moved them out more and turned them a bit---Wow! What a difference! More bass and better imaging. Cost $0. 

@sns 

I have a hard time understanding why anything between the speakers would affect the soundstage:  the sound doesn't come from between the speakers, but rather from the speakers on each side, which, in stereo make it sound like the sound is coming from between the speakers.  Please explain your rationale. 
Thanks. 

@captbeaver

When I go to that Cardas site, it only tells me distance from side and rear walls, but nothing about toe it, etc.  Did you just experiment with toe in?
Thanks. 

Speaker placement charts should all be taken with a grain of salt, including Cardas. None of them can take in account what kind of acoustic treatment you got in your room or the type of furniture and any other artifacts you may have including anything you hang on your walls. Meaning you may have a starting speaker placement with a chart reflecting the size of your room, but in the end you will have to move the speakers around little by little trusting your ears and the toe-in will end up being the most critical decision you make. Be patient, learn about YOUR system and take the time to ENJOY the journey. Being an audiophile is all about testing your system for your ears and not about finding a magic formula on paper.