Not to mention Partisans attack faster than swords, making the reaper deal more hits per minute than the TJS. They might be pretty close, but the reaper is event only.
As for the new weapon, it is quite a hassle to make a new one, you need to alter many files to fully integrate this ingame so it won't be for every event x)
And the L&K38, I've been thinking that IF we'd 'seal' it, and when unseald, it would unlock the combo. But don't count on it, since it requires much changes aswel.
So yeah, fun ideas but don't count on it they'll ever be implemented.