room setup suggesion needed

Typically lots of experimentation is the key. 
 

If I understand your setup. I would try a smaller triangle 6 - 8’ between speakers. Out from the wall a couple feet (wall to back of speaker) or more. Best if there is nothing between the speakers other than dampened wall. The toe in must be experimented with to get optimal wide sound stage without loosing a powerful central image. That takes experimentation. My speaker manufacturer recommends crossing the beams behind the listener’s position. In my room, they sound best with no toe-in. 
 

If you are not used to hearing differences, it can be best to leave it in one position for a month… then try moving… and leave in the better position. Wait another couple weeks… really get to know the sound / soundstage. Distance from wall / inter speaker distance first, then toe in. 

@ghdprentice  I heard before theory of crossing beams behind listening point, and quite frankly I don't understand theory of it, but in the same time I never had setup without speakers toed in. Now setting speakers farther off the wall, what does it do ?

Experimentation is key, and the good news is it’s free.  As @ghdprentice recommended I’d pull the speakers out further from the back wall and closer together, and try decreasing the toe in of the speakers so they fire just to the outsides of your shoulders.  Doing this you may find the soundstage expands and has better width/depth and the speakers may also disappear better as a sound source.  You will lose some wall reinforcement so bass energy will likely decrease a bit but may actually be better balanced so give it some time for your ears to settle in with it.  Really just play with it and let your ears be your guide, but I think you’ve got some significant upside potential here with better positioning.  Have fun!

move the speakers around to different locations in the room and judge for yourself what is best

I adjust and move my speakers 2-3 times a week. Different recordings benefit from different setups, so I don’t think there is one right way. Also, am I in the mood for a wide soundstage or feeling close to the singer, with the instruments in the background?

I play with 5 to 7 feet apart 2-3 feet from back wall, toe-in enough that I can see the outside of the speaker walls. Your room size, speakers are vastly different though.

Now setting speakers farther off the wall, what does it do ?

for rear-ported speakers it would reduce the bass, as far as I know