Huacaya tends to have more dense fiber (they're the poofy looking ones) and are generally more solidly built robust critters. Alpacas in general are pretty hardy little guys, so don't let this make your decision for you. I've never noticed a personality difference. Suri can be more difficult to find, and they have those lovely silky shiny curly locks. Most alpacas are white, but you can find more color variety in Huacaya generally speaking.
As further illustration, here's a couple of Suris in full show coat, probably a year or two of growth. (they're not mine, by the way)
And a Suri in profile:
Here's a nice little Huacaya
I would make the decision based on which fiber you enjoy more and the quality of animals available to you. Personality varies on an individual basis and often depends on how they've been trained/socialized. Maintenance is pretty much the same unless you're showing. And they're all exorbitantly expensive; I recommend starting with fiber geldings, which you can often get more cheaply and are great animals.
I would recommend connecting with a local alpaca/camelid club or 4-H club. They'll usually go out of their way to be helpful and can help you get set up right.