The former England batter believes that the series defeat to Australia need not be a total failure as long as the England and Wales Cricket Board (ECB) use it as a basis for change.
"With the money elsewhere in the game, the [County] Championship in its current form is not fit to serve the Test team," Pietersen wrote in his Betway blog.
"The best players don't want to play in it, so young English players aren't learning from other greats like I did. Batters are being dismissed by average bowlers on poor wickets and the whole thing is spiralling.
"In The Hundred, the ECB have actually produced a competition with some sort of value.
"It is the best against the best, marketed properly, and the audience engaged with it. They got new people to the games and I can tell you that the players will have improved markedly for featuring alongside other greats. It's such a valuable experience.
"They now need to introduce a similar franchise competition for red-ball cricket, whereby the best play against the best every single week."
Pietersen envisages an eight-team round-robin league played in the middle of the summer on pitches that are monitored by the ECB to avoid bowler-friendly conditions.
He said: "We have to have good pitches that reward and encourage strong batting techniques, batting for long periods of time and that require skill from bowlers to take wickets.
"The county system doesn't necessarily need to change. It can be the feeder system below this competition, where players are developed until they're ready to step up.
"I can promise you that the current England team and lots of the best youngsters in the system still see Test cricket, in particular Ashes cricket, as the pinnacle.
"But the world's best players are involved in the IPL, the PSL, the Big Bash, The Hundred, and so on, so it's no good denying them the chance to make their millions anymore, as I was back in the day.
"We need to produce lucrative, high-quality, interesting competitions that reward and improve the best players. This could be one."