You want concealment but you also want comfort.
I've been trying to find the same for awhile but none felt right until last month when a guy I work with gave me his shoulder holster he used in Iraq. I don't know why he parted with it but I gladly accepted.
I've have a dozen different rigs I've tried over the years and pretty much disliked all of them until this one. My buddy said he never bothered attaching the bottom loop to the belt, the gun stayed in place when he bent over and I agree with him.
I know it's a little bulky but I would consider it a winter carry rig over a t-shirt with a flannel shirt over that to hide the strap across the chest.
The company that makes them is: Hill Country Leather Inc out of Hardwood Texas.
http://www.gunaccessories.com/HillCountryLeather/ShoulderHolster.aspI have rigs that are more concealed but the straps all bite into areas after a period of time and I hate wearing them.
I don't like being jammed around the kidneys either with the waist or small of the back holsters I've tried. But a pancake type holster in the small of the back would be pretty concealed for most and maybe a cheap place to start and experiment because I think your going to have too.