...but who to add from Fire Emblem?
Does anyone here know if Fire Emblem 4 ("Seisen no Keifu" or "Genealogy of the Holy War") is still considered the best Fire Emblem game? I'm so sure that Fuuin no Tsurugi, Rekka No Ken, and The Sacred Stones are Japan's idea of the weakest installments in the series that I think making Lyndis an assist trophy was a bad idea.
If the people who've played FE4 think it's better than Path of Radiance, Radiant Dawn, and Shadow Dragon, then I propose to add the main star, Sigurd, as at least an Assist Trophy.
And we all want different "obscure" or "surprise" characters in Smash 4. For mine, you have to look at where the Fire Emblem series started. Among the last enemies defeated in Fire Emblems 1, 3, and their remakes was a dark Earth Dragon named Medeus. The fact that the Fire Emblem creators (Intelligent Systems?) have done nothing but remakes in the past 3 years is further justification.