I think you'd have to have pools based on timezones and then finals.
This also runs the risk of leaving cricket in the same state as it is - high viewership for the Indian sides and whoever plays them, and lower viewership for other pools. I imagine the European Division and the Oceania Divsion will have some decent veiwership thanks to England/Aus/NZ, but who will tune in to watch Guyana play Florida or Natal play Namibia?
Less viewership, less moneyz, lower quality of cricket. Won't be a big issue if the idea of Salary Caps is accepted by the BCCI, but if it is a open market where franchises pay what they want, then all the talent and money will continue to be concentrated within the subcontinent (particularly India) and we'll continue to see declining standards around the world.
At most the BCCI will regulate the salary that each side within the Indian Leagues pays out -for the sake of competitive cricket- but they aren't going to agree to their sides having the same budget as sides like Jamaica and Colombo.
Also the finals will have to be played in India/India friendly time-zones, just because it would be crazy to play them at a time that the largest audience in the world won't be able to tune in. And as we've seen with the Champions League, the BCCI will try to shoehorn in more than their fair share of teams into the Finals.
I think for Franchise-based FC and OD cricket to really be viable, it has to be based in India. Or at most, within India/Australia/England. Just because the other regions will not sustain the kinda of viewership needed to make it lucrative.
At most, I suppose, you could have a European League, an Indian League, and an Australian League. Their seasons will all slightly overlap (June - Sept/Oct for Europe, August - Nov/Dec for India, and Oct - March/April for Oceania), and the Indian league will most likely be the richest one, but this way you capture the three biggest time-zones, you have cricket all year around (allowing for a player to play for multiple teams), and you provide enough teams for the talents from the lesser nations to be able to find someone to play for. Give these games FC/OD status and let each tournament decide their own salary caps and foreign player restrictions and such.
Then once in a while you can have the marquee International events - maybe a Test League than runs on a 2-3 year cycle with 2 divisions, and then a large World T20 (20+ nations ala the Football World Cup) and a concentrated ODI World Cup.
Realistically speaking you'd need to have some sort of global rankings or seedings that allow the Big 8 to have direct entry into these events regardless of how crap they are, and then qualifiers for the rest of the nations to prove their worth. A 20 team WT20 may very well be 20 minnows playing for the right to qualify for a main tournament with the Big 8. You also don't want the possibly for India/Aus/Eng getting knocked out early, and you don't want them getting demoted in the Test League. This I feel will lead to some set of rules/regulations that won't make it much of a fair competition (maybe a point system to encourage defensive cricket so India can avoid relegation by just stonewalling their way to draws on flat pitches, or a regulation that says these 3 are immune and the lowest points out of the remaining 5 will relegate instead), but hey, it will be a start.