a usable, simple, widely accepted p2p currency, involving no money changes (ie fee free), with no centralised control, that retains a stable price.
I saw a guy in the exchange trollbox yesterday that said he left money in BitUSD (the Bitshares dollar peg) for something like 6 months, came back and it was still there, same dollar value as before. The market pegs for a stable currency seem to already work. I believe Nubits also has a dollar peg, but I don't think it's as good a mechanism. There are many ways to do it from price feeds, to market maker, etc.
Now, if you think DPoS is the future, then there's plenty of room for that too. You'll probably be able to spend it the same places you can spend Bitcoin.
I don't think this statement is correct. If systems such as Bitshares DPoS and Emunie (like I said, if Emunie actually works), gain the same widespread adoption as Bitcoin, Bitcoin will be dead pretty fast since it handles 0.00007% the transaction volume and 0.00167% the speed with probably more expensive transactions on top of that after the miner subsidy lowers.
This is probably why if you go in Poloniex trollbox right now and see six lines of text in a row, five of them say they're long Bitshares, and the sixth will be something like "Where did the Ethereum volume go???"
Volume on BTS just went to the moon equaling Ethereum, but it's still trading in a small range, meaning someone is accumulating and not trying to maniacally push it up. Seems like Ethereum people are diversifying.

A quote from a different thread:
Pretty much the only thing crypto needs less of is get rich quick cock jockeys and attention.
Can't even imagine how something so stupid (Bitcoin) made it to be worth more than some small to medium sized pharmaceutical companies.
He must not read Zerohedge. CNYK, the company with 1 employee, 0 revenue, 0 assets, and no product made it to a five billion dollar market cap. We probably haven't even seen a real crypto bubble yet. The thing about the so called 2.0 platforms is, they have the advantage of being more than currency, being able to run decentralized exchanges, derivative products, USD pegs, store integration and payment processing, etc, so they can kind of blend in with normal items traded on Wall Street. Meaning even if Bitcoin died for some reason, and people suddenly don't trust cryptocurrency, some platforms like Ethereum and Bitshares would still exist. With the asterisk *if Ethereum develops into a platform with a valid consensus mechanism to support it and economic activity since I don't know what it's supposed to be now.