I was actually a HUGE fan of Radiant Dawn, and I gotta say, Ike and BK don't really fight the same way at all. They do have pretty much the same sword, but don't you remember the animations from the original game? Black Knight/Zelgius would always just lumber over slowly and then hit like a freight train with a single blow....EXACTLY like the assist trophy. He was a heavy knight after all. While Ike may be one of the more brutish FE characters, he's still got leaps and bounds more agility than BK, flipping around with his Aether. That said, I think that if BK got into smash, he'd deserve to be a unique character rather than just an echo of Ike. He could be similar to Ganondorf, slow as hell but INSANELY powerful and heavy, literally killing light and medium characters in 4 hits or less. These kinds of traits would make him notably different from all the other FE characters. I'd also love it if some of his palette swaps were General Zelgius without the helmet too. Gotta love that hair!