The format at the moment is shite. There are loads of ways they can improve it without any teams having to drop out. I'm sick to death of the clamour for 'franchise' cricket over here - it won't work. Folk from Liverpool won't support Manchester just like those from Sunderland wouldn't support a team labelled Newcastle.
I'm yet to see a list of 'franchises' that would keep all counties happy and that is the ultimate aim in terms of getting the necessary votes. Any team who missed out would have to be compensated financially for potential loss of revenue and the only way that would happen is if all money made throughout is shared evenly and I can't see the likes of Middlesex, Surrey, Yorkshire, Lancashire (basically Test Ground based teams) being happy to share money that they've made through their own support and publicity.
For me, play the T20 over 4 weeks of the kids school holidays, so it would be finished by the football seasons start date and it would allow parents to take kids without worrying about them missing any school or being tired for the next day. Have 3 groups of 6 (home and away ties) or 2 groups of 9 (play each team once). Allow 4 overseas players per side - even though some sides will struggle to afford 2. There must also be cheaper tickets made available. £10 maximum for adults, with family offers available - that's one big reason why the BB is popular, the tickets are dirt cheap.