I've been wondering about Way of the Horse, since we know what Horse does already. It assume it would have something to do with card draw, but it obviously can't just be the same as Horse's text. +2 cards seems like a possibility.
I think the design challenge with Ways is how well they work with any Action card. Turtle, Rat, and Chameleon all scale to the card that is playing them. Ox and Mole don't, but are situationally useful: if you have three non terminals in your hand, you're going to activate Ox, and similarly if your hand is a $5, 2 coppers, and 2 estates, Mole looks attractive.
I'm hardpressed to find frequent enough examples of wanting +2 Cards in lieu of the card's regular instructions.
How about: "Discard this. If you do, gain a Horse per $1 it costs."
So now a $2 card is a deferred Moat (one at a time, of course), while a $5 card gets you +5 deferred cards.
(if this is too strong, you could possibly replace "Discard this" with "Return this to its pile".