Odd Rhythm: C. Nowi, Nah, and Tiki don't get -that- many better skills, which stops it from being a total D. Odds are (pun not intended; I caught it while proofreading,) it might survive through a reclass or two.
Wyrmsbane: D. Listen, I'm sorry, but if your Manaketes aren't wrecking dragons just fine without this, then why are you even fielding them at all? I could easily see making an argument for it if it wasn't locked to Manakete (to give their other classes an edge with their Bronze weapons immediately after reclassing.) Honestly, this skill exists for Spotpass Tiki (and perhaps a player's spotpass Nowi/Nah) to harass you with, and not much else.
Ultimately, when Nowi/Tiki can get access to skills that replace these so easily - even before getting into what Nah (and Morgan!) can inherit, they're basically just there until they're replaced.
For the record, on my newest file, Nowi has Lifetaker, Bond, Focus, Swordbreaker, and Rally Heart (Just for the +1 Move if the party splits up; I have a better Rallybot) while Tiki, Nah, and Morgan (mother undecided) remain unrecruited.
PSN: Ranylyn. Mass Effect 3 Adept/Sentinel/Engineer Currently Playing: Fire Emblem Awakening. Tactician: Ranylyn