I'm using SC-III's in a similar sized L-shaped room. They sound very good, but I know I'm not hearing their full potential. I think the recommended placement is at least ten feet between speakers and an equal distance to the listing position, toed-in sharply. Placement on the long-wall is also supposed to be best, but obviously not an option for you.
I had very good results treating the first reflection points at the sides and ceiling with 3x3 acoustic foam tiles. More room treatment is likely to help.
I also put 2x2 brass cones between the plinth and my carpeted floor and got a nice improvement in clarity and focus.
I'm now in the midst of a crossover upgrade. I replaced all the sandcast resistors with Mills wirewounds and next I'm putting in Auricaps in place of the stock Solens.
I had very good results treating the first reflection points at the sides and ceiling with 3x3 acoustic foam tiles. More room treatment is likely to help.
I also put 2x2 brass cones between the plinth and my carpeted floor and got a nice improvement in clarity and focus.
I'm now in the midst of a crossover upgrade. I replaced all the sandcast resistors with Mills wirewounds and next I'm putting in Auricaps in place of the stock Solens.