regards the vitamin B6...i've been taking a vitamin b complex for the last couple of months, not for the purpose of dreaming, simply because i realised i was deficient in it...however, in the last couple of weeks, i have noticed that my clarity has greatly improved, images are much sharper and clearer, and therefore easier to remember.
By the way, welcome to the board!
I hope you find it useful.
And with regard to recall, i've always had pretty good recall, but i do find i get some nights where it's horrible, and i remember very little. And other nights i'll have two or three dreams.
I don't know why my brain does this, but i have found over the past few months that the best thing to do is to not worry about it too much, or it becomes a self perpetuating cycle.
My dreams always come back to me eventually...