Your "LTC as a backup" argument has never made sense to me.
LTC would fail as a backup because it offers no security balance, and will suffer the same hypothetical fate as its bigger brother. Think about it: if the bitcoin network were suddenly brought to its knees, how would anyone be safer in LTC?
AEON backing up XMR is equally absurd.
I'm no LTC fan (as it has lost it's initial goal, ASIC resistance) but I see where it could survive where BTC would fail as it is still far more decentralized. I really think they should hard fork to a ASIC/GPU resistant algo though. Just in doing it once would show that they would be willing to do it again if ASIC's are designed for it again. But I think that bus has left the station and in the coming years LTC will be right where BTC is now. Doge merged-mining has really helped them though I would say as far as security goes but I don't see that happening again any time soon and will become m00t when difficulty gets high enough.
Yeah, Aeon backing up XMR is an absurd thought. What Aeon should do right now to set itself apart and become a contender for an actual usable currency is... I'm not going to say unless I decide to get in it.
![Tongue](https://bitcointalk.org/Smileys/default/tongue.gif)
1% of your XMR gets you into Aeon for the same stake.
I also think that it is unlikely that Aeon will ever obtain significant market usage? Is it worth a 1% XMR hedge? In my opinion, absolutely. If something goes wrong with the RingCT XMR fork (very unlikely but always possible), it is nice to have a solid CryptoNote backup network.
For network security I would suggest mining Aeon (solo mine) instead of buying.