I never had a PoS coin in my portfolio and never will have one. PoS is not backed by anything other than the belief there are worth anything and there will be an endless supply of PoS coins because one created today does not have a significant advantage over on created tomorrow, next week, next month.......
What currently is happening is new coins are created with PoW, mined for a week until a fixed number is reached and then change to PoS and then you can claim your stake at buying xyz coin. The only advantage a coin released today has over on made sometime in the future is, somebody already bought into it. The advantage quickly disappears if the new coin has a better catch phrase a flashier webpage or bigger marketing capital....There is no end in sight for stake claimed coins and all promising x % return if you know a bit of programming you will have your very one coin too and everyone can buy into your claim based coin.
Its a barrel without bottom and once it clicks run for the hills if you own a stake.  
    
A new pure PoW coin can not compete with existing once on the market unless its cheats in some way by instamine, premine, ninjamine or some other scam which then prevents it form growing. The inflation handicap will always be with Litecoin in regard to Bitcoin and so it can not get in front, and equally stops new pure PoW coins in its tracks. Inflation also works in favour of Dogecoin in the short term so merge mining puts Dogecoin in a favourable position.

PoW is backed by energy. There is no better backing than energy because everyone needs it, wants it and i will never have any problem selling it. To create a PoW coin you need x amount of energy and you can not cheat. The best you can hope for is to have  a more efficient miner. Because the energy has been spent the coin has a base value (many other things on top) and is a kind of a storage medium.

Mark my words