While I would like to see more final destinations like BTC seems to be, it is a bit of a headache for exchanges to put every coin against every coin, and potentially an interface confusion for consumers/users. I think the best thing to do would be to add a couple more coins to value comparatively... the problem with that is deciding which, as 99% of them are extremely unstable and fluctuate in their own value by the hour. There's a couple that are becoming more stabilized, but need a bit more time to see if they settle in.

http://www.coinwarz.com/cryptocurrency shows stability, but that's up for interpretation and bias. It's possible coins like WorldCoin and DigitalCoin might get to that point, just probably not yet.

TL;DR I agree more coins should be traded against others, but that's hard to do and/or confusing... for now. When some of these new coins stabilize, they should be able to convert to whatever (including fiat) without going through BitCoin first.