I'm struggling to see the importance of alt-coins. It seems to me that one of the major selling points of the various alt-coins is their quicker confirmation times. The common argument is: this is good for merchants and the like, because there is less time for them to worry that the customers' payments are legitimate.
But can bitcoin users not have the same "luxury?" Why can't a merchant run his own node? His node will process the transaction, and the rest of the network can play catch-up.
Another argument is that there are too few bitcoin, and that eventually bitcoin will be the gold of digital currency--what the big transactions happen in--and the alt-coins will be the silver, or the copper--for day-to-day use.
Is that really even good in theory though? The price of bitcoin would need to be in the millions for that to even be a decent worry. I can possibly see it being an issue, but do we really need to consider it now, when the exchange rate for bitcoin hasn't seen more than a few months in the 4-digits?
Am I overlooking a hyper-important advantage?