aliasing in an ESEA match is kind of silly. especially if you're the new hotness in town like downpour(joonna). you have to think about branding, baby. some viewers/fans will only tune in to a match to spectate their favorite player. why make it difficult on them, the casters or any potentially new comp players?
however, i agree that aliasing outside of matches is sometimes necessary as unwanted attention in pubs/pugs/mge can get annoying.