If you guys are sending mails to senators , consider raising point about chain migration as well. Clearing huge backlog in such a short time for the people from India and china , will also add large number citizens 5 yrs down the line. People from this part of world have tendency of sponsoring their relative as soon as possible. It has potential large chain migration down the line. Senator has already raise this point but you can tell your senators that large number of immigrant in short period of time is your concern.