"It would take immense amounts of venture capital money to build a direct competitor across all those niches."

Wait. You don't need to. Niches actually make it easy to take apart. Concentrate on one niche and do it better, faster, and cheaper than Bloomberg.

Having been in finance, there is a lot of unhappy Bloomberg users. The organization itself, however, is pretty top-notch. They have some really brilliant people working there and the customer service is quite good.

That said, I think in a classic innovator's dilemma scenario, one could build a company that has very few features but does it well and don't actually need to provide support. More importantly, do it for cheap.

Then again, "cheap" isn't usually what finance companies look for. The inefficiencies of that industry is staggering. So long as they come out ahead, it might not be worth it for them to save some money but have to live with limitations.

So maybe the right approach is to target some segment of the finance industry that cares only about a niche and has to really watch their bottom lines.