Martin Crowe, the former captain of New Zealand, thinks the ICC should focus on Test and Twenty20 cricket and give up on the 50 overs game.
Crowe also thinks a Test Championship will give Test cricket a bit more purpose:
We have to get to a point where we are hosting a Test Championship final, and those seven games will become the great focus throughout the course of the year for all the media, the fans and the teams. It also gives all eight teams a chance, over six days, to win that Test match and progress forward.
[...]
At the moment, you have World Cups, Champions Trophies, World Twenty20, the IPL, the Champions League, all these shorter formats are up and running, dominating the landscape, and they all have a meaning and they all crown a champion. But Test cricket, which is the pinnacle, is the purest and the best form of the game, doesn’t have anything.
via Cricinfo.com
Another notable thing is that Crowe mentions six-day Test matches to make a result more likely.
And last but not least, Crowe states the importance of moving the game forward by introducing day-night Test matches:
Test cricket needs a lot more work from the marketing point of view, and that’s where day-night Test cricket must be trialled soon. [...] It won’t suit every country and the conditions in some countries won’t allow it. But I certainly think that in some places it will be wonderful for the local market.
So more than just one of my 5 steps to make Test cricket better. (I never claimed to be original, did I? 
) But I do believe a lot could be done to make Test cricket better without changing it beyond recognition and these five are the best ways to do so.
What do you think? What are the best ways to make Test cricket better and what should Test cricket look like in the year 2020?
I think it’s a bit of a disgrace that he, a New Zealander, is calling for the end of ODI cricket when New Zealand Cricket has survived only because of 50-over cricket. How many people go to Test matches in NZ? How many go to ODI matches in NZ? I rest my case.
In that light it does seem a bit strange Crowe would support such measures, but on the other hand it could also be a sign of how much he believes in these proposals.
Even if it might harm New Zealand as you suggested, Crowe is looking to improve Test cricket as a whole.
That is not such a disgrace, is it?
No, it isn’t a disgrcae that he wants to improve Test cricket, but it is a disgrace that he’s wants there to be no more ODIs.
I don’t know. Is there room on the international calender for three formats?
I do like ODI’s, but I also think there is too much cricket being played internationally and choices have to be made. And if I had to make that choice, I think I too would chop ODI from the calender.
Twenty20 is by far the best way to promote the sport to newcomers and Test cricket is the finest form of the game, so that is definitely staying
What I do think is wrong with Crowe’s suggestion is the format of his proposed Championship. The top four ranked teams hosting the bottom four in quarter-finals is too much fuss. Just let the top four play it out amongst each other.
Also, I think introducing such a Championship should come with Test cricket being part of a competition format with multiple divisions including promotion and relegation play-offs.