This is a fighting game and the last time I checked swordsmen are fighters. And from what i've seen they all play completely different, some of them just use the sword as a secondary weapon.
Link - Has an entire arsenel of different weapons
Ike - Strong, heavy sword figter
Marth - Quick, light swordman
Robin - Mainly uses magic
Shulk - The monado has a bunch of different techniques
Lucina - Probably the only odd one out since she's a straight sword fighter with nothing special
So why all the hate exactly? What would they prefer though? More troll characters that aren't even suppose to be in combat like the Wii Fit trainer?