Your way is probably a good method for a new modder. For the reference, though, I personally prefer to do all the modeling first, texturing each unit as I do it, then do the XMLs, using a static model. I usually make the folder layout and such from scratch, but generally copy a template XML and then just tweak the values, to save time in typing out all the syntax, not to mention it helps prevent errors. Once satisfied with the XMLs, I'd animate models, then get proper icons created (I'd just use placeholder icons before then). Sound is the very last thing I do. I usually plan out the names of the units, where they're produced, requirements, commands, etc on paper before I even start making the mod. The reason I do the modeling and texturing first is because I'll usually end up going back and tweaking various parts of those as I improve them (it can also be a pain to tweak the model of something once it's animated).