I think immigration is an awesome tool to have in our bag as a nation and I would hope to enhance it as much as possible. That being said, a nation must be permitted to secure its borders. In doing so, immigrants must come in in a legal fashion.
I don't subscribe to the idea that most of those who come in illegally are bad people or commit crimes (beyond the illegal entry) at a higher percentage than most. I also don't think that they abuse the welfare system for the most part. That being said, they still have to go through the wickets or risk deportation.