I love how utilizing his authority to pass executive orders is suddenly "bypassing Congress and the constitution" just because its Obama doing it.
He has looked at his authority under the law, and concluded that these are the steps his office could take unilaterally, without intervention of Congress. Seems to me like he's paying close attention to exactly what actions are within his authority and do not offend either of the institutions mentioned. In fact, that's precisely why he's taking this specific set of actions.
All in all, Republicans are just trying to eviscerate Obama at every turn. He could have come up with virtually anything, and it would have been shouted down by Republicans.