I also blend different systems together; my needs vary and sometimes a simple folk spell with candle and the Psalms might do the trick, other times full ritual magick suits the bill. Think of the Art like Fine Art, or Music, or any sort of creative form of expression. You can imitate established masters' styles and methods, but the only way to really give true voice to your soul, to your essence, to meet your needs absolutely is by developing your own methods. And if that means mixing different trads and systems, hey, if it works for you, that is all that matters, the bottom line is results. But that is me : )