Most celtic music is as you described. But it is often played in an AA-BB-AA-BB pattern. I bought "Slow Airs of Ireland" and there is a ton of free stuff under the "Traditional" heading for free sheet music.

I've played a DC PRO alto flute and I must say it was awful. The key metal was so soft that the keys wouldn't close all around, they were not strong enough to hold their angle/shape, and the lack of pointed arms compounded the problem, as did the long distance between touchpieces and actual pads.
I played a Justflutes alto which is a much better design (has touchpieces over the pads, pointed arms (which really matter in altos) and also much stronger metal.
I have to say the sound of the DCs was not bad though, just badly designed... But with an alto flute I say the body is more important... You can buy the pearl head with silver lipplate for 200$ if you want a better headjoint.
Anyone played Allora alto/bass flutes?