Is anyone in the investing/finance niche?

Ok so me and my friend have a deal where he will write an ebook and I will set up the website and do all of the traffic driving and marketing, etc. (he is a stock market whiz - he's read like 40 books on investing and spends all of his free time reading news headlines and analyzing). So, we were deciding whether to make our product:

1.) A complete guide to his investing system - industry research, company research and analyzing, predictions, when to buy/sell, etc.

2.) Something more specific in this broad niche.

There are many, many products out there like option 1, so we would have a lot of competition. So, we were considering option 2. The first two subniches that come to mind are investing in penny stocks and short selling. My friend, for some reason, does not like penny stocks, so he has not spent a lot of time learning about them and investing in them (he's messed around with them in simulators, but he's never actually invested real money in them). So, we could not write an ebook about penny stocks. So, our focus shifted to short selling. So, I first went to clickbank, and I actually couldn't find one product based on short selling. I could only find stock market robots, complete systems, and products about penny stocks. I then went to Amazon, and found a few books, but the highest selling book was ranked at like 16,000 out of all books, and the rest were 30,000 and below - and dropped fast as I went down the list. I finally went to the google keyword tool and found a list of keyword phrases related to short selling and typed each into google to see if there were any google search ads for the keywords. Almost none of them had a single ad.

Does this mean that there is no money in the short selling subniche?

So, I am wondering if anyone else has products or websites in the investing/finance niche, and if so, would they mind sharing what their website/product's subniche or focus is?