I guess I don't know enough about the War of Roses to see much parallels to it in the series, except in the vaguest of terms if you suppose that Daenerys is a would-be Henry Tudor aiming to reinvade Westeros to reclaim the crown taken from her ancestors. The historical parallels that jumped out at me much more are with Ancient Rome and the early Islamic empires, respectively (the former is a detail, the latter a major plot point in a future book). Oh, and obviously the one with Hundred Years War France. And I suppose you could argue the Dothraki are modeled on the Mongols to a considerable extent, more than any other horse nation... looking for historical parallels is fun.