Personally I've found most arabians dislike single jointed bits, they can give reason to toss heads, as the bar forks at the top of there mouths.
Also, my experiences are they prefer bitless..
My alfi, takes all my attention, he loves to be with me, now lives alone and prefers to choose his company, yes I agree, arabs need plenty to keep there minds active, they do get bored easily, even spending the day in a field, my alfi would get bored, even with companions.
They need stimulation and friendship. Also, I find, routine is key to all..
Also, no need for high quality feeds, keep to, low sugars and starch.
They let you know when somethings wrong and many rewards when things are right.