Honestly? I think it is pretty funny that he's batting away bullets with a sword and playing Knife CS.
Games aside, once you close on a rifle or pistol wielding opponent, it becomes
dramatically more difficult for them to hit you, and easier and easier for
them to get killed with a knife. It's 21 feet (6.5 meters). It's something everyone in the military gets taught. CQC is a very valuable skill.
Considering Kuroyuki's family relationship hinted at in the series...there's pretty much no way. The author would never take his Gary Sue and especially his Saintly Maternal Yamato Nadesico and have it work out that way. It makes sense, but it also very much
doesn't.
All the exposition in this episode made it a very strong possibility that Kirito is the developer of the Neuro Linkers and maybe Brain Burst itself.