I like the prem logo, because despite having a lion, it fits the name. MLS' name is Major League Soccer, and has no country ties. English premier league does. More that that, Lions are universally seen as a sign of status, royalty, kingship and it naturally compliments the word Premier. So its not only works as a national symbol, but also as a dual thematic. By using a lion, the premiership truly comes off as soccer royalty.
He new MLS logo has no similar concept of thematic storytelling beyond the colors and Stars and Stripes.
Which is its biggest failing as a logo. It failed logo creation 101: tell the audience what the product is about. If I werent an MLS fan, and I saw that logo by itself I would have no idea what it was. A new clothing brand?
Adding them long slash and it just looks like something a college graphic designer student would come up with for fake logos in branding graphic design class that would earn a B-, maybe C+ from their prof.
Lack of unity, lack of theme, lack of message. If I were that teacher I would give that logo a C-. Never mind the fact that the logo represents a sports league.