The whole point of alt currencies was that they could bring some features to bear that BTC did not. For example Primecoin has a functional benefit for mathematicians. If nobody ever uses the coin other than to make money then it will become adopted and will be worthless once the initial surge is over.
Having said that you can make $ with alts, but it requires time to trade them. Trading requires exposure to risk of having currency sit on an exchange.
Buy BTC with the $ you're not willing to gamble with. Buy your favorite alts with whatever you're willing to put on 23 (or whatever number) on the roulette wheel. Alts can run up like BTC too, but I can't see any of them being used to trade like BTC (at least until somebody sells a Porsche for LTC).
Thanks for the tip. Primecoin seems like what I'm looking for (Anti ASIC and GPU.)