Lack of strategic guidance, lack of political guidance, bureaucrats who care more about empire building than actual intel work, too many desk jockeys, too much insular culture, too much money in the wrong places, too little money in the right places.
Essentially, we'd need to come up with a coherent plan, find people to implement it, RIF the folks who can't implement it and keep a firm hand on the helm to ensure the plan is followed.
We need two missions.
Stopping bad folks here in the States, keeping an eye on the world at large.
Biggest counterintel threads are China, Israel, Russia and rogue individuals or non-state-sponsored groups (in order). France is an odd fifth. al Queda is not flipping many Americans, or trying to steal our stuff. They want to cut an American's throat, not flip him or her to work for them.
Intelligence wise, we need to have a "feel of the streets" level everywhere. Obviously, we need to be tactful as the two main intel threats to the US are nominal allies, and theoretically Russia isn't an enemy either. It's wise to remember that a country and its intelligence agencies are very different critters. We can be enemies with a country and friends with its intelligence agencies, or vice versa.
Honestly, the real trick would be to quickly get information in the right hands. We lack that capability and no one is interested in building one. Instead we get friggin' huge patchwork of piece meal solutions.
Example would be that the underwear bomber's dad called the US government and let us know his kid was off his rocker. A lowly Embassy desk clerk should be able to submit that info to TSA, FAA, CBP, etc. They should have access to read, but they should be able to push data. Could be true, could be BS, but it's enough to warrant an extra special screening.