Ok, I am attempting to make a block that when accepting a redstone signal, it will propagate that signal to all adjacent blocks, but NOT the block it will be receiving the power from, to avoid it all getting stuck on. In other words, how would I go about checking which side of a block the rs input is on? My only thought would be to have the RS input make it change metadata, and then upon adding RS output to each side, it first will check each side to see if that adjacent block is already powered... but is there maybe a more elegant way to do it?

I see no problem, I would do it in the way you'd described I think .