There's no way that MLS would be supported in Charlotte. I'm not knocking soccer, but I don't think the fan base will support it. Arena football disappeared in CLT and I bet the Charlotte WNBA team is not a money maker either. Football, basketball and baseball are the 3 major sports in the US. MLS soccer has come on strong over the past years but the newness would quickly rub off and attendance would fall in CLT.
I have a feeling that if the Knights come to uptown, then you can forget about a MLB team coming to uptown CLT. That is unless they are capable of expanding a minor league park to a major league park. Or not having the MLB tean in uptown.
Does Charlotte have the fan base to support 80 or so home games over the length of a major league baseball season when most of the games are during the week in the evening? I don't see many people willing to drive from Greensboro on a Tuesday to catch a 7:30pm baseball game in Charlotte.