my advice is to allways work in .psd format and keep decorative stuff in a layer separate from the surface it is on. that is both woven decorations on tunics, painted patterns on shields, etc..
then simply save a .dds with all these layers hidden, that is your base for a good normal.
and the result is, well you seen my .psd`s - they are full of unnamed layers

to prepare the bump map i use some unsharp-mask to over amphasis details and also some contrast to the same end. i usually use a bump level of about 6 and then gausian blur soft or shiny details such as faces and swords.
for the normal alpha channel i first turn brightness all the way down, without legacy mode enabled. then i use some contrast, with legacy mode enabled, and then darken the whole bit so that only shiny parts are visible.
but also you can PM me your files and i see what i can do.