Alt-coins are the only way BTC avoids being an inefficient monopoly. Competition is almost always a good thing. Though maybe it would be good if there were only 3 or 4 alt-coins. I'm thinking maybe just LTC, FTC and Peercoin. More communities working on solving the challenges of cryptocurrency sounds like a good thing, though they are mushrooming too much.
BTC would never be what is now, without altcoins. You have to admint that
What do altcoins add that Bitcoin needs?
Alt-coins provide an easy store of value when speculating for example. Many exchanges allow BTC/LTC currency pairs and while BTC is volatile LTC and FTC seem to hold steady around 2.1 $ and 0.0004
BTC respectively. So when BTC is low you buy BTCs in cash and then when it spikes you sell it for LTC. Then you remove the necessity of cash from the trade, which helps given the difficulty of getting fiat currency into the exchange quickly. So it's not BTC that needs alt-coins, it's just that alt-coins make it easier for BTC trading and eventually supply.
Thanks for sharing, thats what I have been trying to do but always went in too early...