personally i don't bother rotating as it equals out in the end (and it's less work taking them out every week lol) i'd maybe suggest thinning out a few fan leaves if they are blocking cola's but don't go mental and strip the things to the bone.
you could tie it across to the front corner yes, or pinch and bend the cola, or again as it is in the corner just let it be, it won't be blocking light as there's nothing behind it. is the tall one QQ by any chance? looks like it from the structure.
as for yield, too many factors at work to even guess, what are the strains, how much hps you running and what are you feeding them? even if i knew all that info i still could only guess dude!
all in all great looking grow man!