Ultimately I think the model we have is broken precisely because of what you describe: the FTC can’t “get it right” every time and many bad mergers will slip through the cracks.
I think a dramatic redesign of the M&A system needs to occur.
For example, I think a merger/acquisition ban for companies of a medium to large size could be an effective design of our corporate system. Most medium to large sized companies make acquisitions and mergers out of convenience and a desire to thin out competition rather than any sort of business need.
A company like Apple or Google or perhaps even a much smaller one should be disallowed from acquiring companies or being a part of a merger from the standpoint that they are sufficiently large as an entity.
Examples like the Apple acquisition of DarkSky and Beats or Google’s purchase of Nest represent companies who clearly have sufficient resources to build a competitor and new entrant to the market internally, but out of the economics of the arguably lazy M&A shortcut they are allowed to buy competitors and remove choice from the market to the detriment of both customers and the labor market.
In short, we’ve just accepted the base assumption that companies are allowed to buy each other at all and that entire concept is worth questioning.