So your room is 10f long. It is short – there no doubt about it ! On other side – nothing wrong with using SL in near-field position ! I luv it !
On your place I would go 3F from front wall, you will sit 3F from speakers and you will have 3F behind!
For SL lovers:
Sidewall distance from wall to speakers meaning nothing
About toe in:
I found that middle of the speakers should face your shoulder on your listening chair. More toe in – more highs, more dynamics but narrow soundstage .. More out – wider soundstage, loss of focus
How you gonna do it ? In dark , take flashlight and put it on the middle of your head – look at speakers and be sure you see reflection from the myler to be symmetric to your position.
Also! Do not spread SL too far apart! You will loose bass and dynamics ! Even if they are close to each other – they should make soundstage wall to wall!
I told that Joe Cohen when he exhibit his amazing cables with SL at California show I think year or two ago when he complained that they could not get bass from SL .. IMO SL were to far apart ..