The England and Wales Cricket Board wants to introduce an innovative '100 balls' format into its new eight-team, city-based tournament.
The concept could see innings consist of 15 traditional six-ball overs, and a final 10-ball over.
That would be 20 balls shorter than traditional T20 matches.
Those devising the competition believe a 100-ball 'countdown' would attract new audiences and be popular with broadcasters.
The proposed approach was presented by the ECB to the chairmen and chief executives of the first-class counties and MCC on Thursday.
ECB's chief executive officer Tom Harrison said: "This is a fresh and exciting idea which will appeal to a younger audience and attract new fans to the game."
The new competition's board unanimously supports the development of the 100-ball concept.
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Southampton, Birmingham, Leeds, London, Manchester, Cardiff and Nottingham have been selected as venues for the five-week competition, which starts in 2020.
Both Lord's and The Oval will host newly-created teams in the competition with the Ageas Bowl, Edgbaston, Headingley, Old Trafford, the Swalec Stadium and Trent Bridge the other grounds chosen.
The BBC and Sky Sports will broadcast live TV coverage of the new men's and women's domestic tournament each summer from 2020 to 2024.
The new competition will take place alongside the existing T20 Blast which is expected to be unaffected by the proposed format changes.
The ECB believes the concept will help to appeal to families and a more diverse and younger audience, and provide some distinction from the T20 Blast.
It will feature aligned competitions for both men's and women's teams, with the same format and team identities.
The 100-ball concept will now be further developed but it has been welcomed by the broadcasters and player representatives - both men and women - that have been consulted.
