My past experiences with Subaru and VW tell me "get things done right, not cheap" so here I decided to do it properly after all. 
I discovered that my shorty downpipe is not a good idea without intermediate downpipe. Given I don't even have 2.5 inch cat exhaust, the whole Stage 2 on this setup would probably be a dumb thing to do. I said "screw it, I'll buy all the right things". Miraculously, I found a $399 SPT catback, same one I had on my old WRX TeaR; I successfully secured that through ebay bidding.
As far as downpipes, I am not sure yet. It could be COBB, Perrin or something else.
Check the picture of the downpipe I have installed now:
Compare it with the downpipe I had on my 2006 WRX:
Finally, since I peeled Geoshield film, it was time for me to apply proper one. Car-risma once again proved to the best deal around as far as price and quality. So now I have SunTek High Performance Series film 35%+15%. Very happy so far. 