I'm a fan of all platforms. Ethereum is just our best case study since it really is our ONLY major case study of a platform as of the moment hehe. Of course OMNI and Counterparty also have coins residing on top of them too and have further potential down the road along side others who are still waiting for their first set of Dapps.

As for Bitcoin, Litecoin and the rest of the 'currencies' their upside is tremendous and for what they can do to digitize currency is a game changer unlike any other specific space. As such I do invest in it. However, beyond currency I am limited in the non platform based projects I invest in for sure. GridCoin is one such fav. :)

As for overall valuation if you look at all of the coins sitting on top of the Ethereum network plus Ethereum itself you might be surprised to see that the Flippening happened last month. Of course a year or two down the road I think that it will become obvious :)