Sorry for the late reply but its been very hectic at work....
Now, as far as I know there are no packaging materials that you can use and produce bacon "in one step"... unfortunately the high fat content as well as the brine you inject wont stay inside the pork bellies. Hence (as you probably already know) there is no point in direct smoking or use of "pre-smoked" packaging materials because at the end of the process you will get a product that, at best, has patches of smoke and is not uniformelly smoked...
The only way I know, is basically the process you currently apply, with all the drawbacks that come with it (too much labour, contamination hazards, too messy when unpacking the bacon slabs etc...)....