
One thing I'm not sure about, though: you say that you PyFFI your Oblivion bsa. No problem so far. But then you say that you omoded it! Last time I PyFFIed those meshes, I rebuilt a bsa file with OBMM. Is there a difference?
Yes. First off, for building bsa's, I recommend BSA Commander. You can specify the flags with it. OBMM uses common flags which are not correct, according to the vanilla bsa's. The main advantage of OMODing or BAIN packaging is ease of deinstallation. I read somewhere that bsa's have advantages besides cleanliness and compression, but I don't know what they are. Someone more knowledgeable than me may know.