The problem with ranked choice voting, and even approval voting:

[eniwetok]

2. how do we get the Democratic Party to agree...

As I wrote elsewhere in the current, rather antiquated electoral and political systems, as a progressive I can vote forever and never get full representation for my beliefs... and I'm rather lucky to live in MA with Liz Warren and Ed Markey as my senators.

But any citizen has more than one or two realms of interest. For instance both of my Senators pretty much mirror my social interests in extending civil rights. Both are economic liberals who oppose free trade and want regulation on corporations. But neither really supports my political interests... that is for finally making our state and federal systems truly democratic.

Liberal Dems need a 50 year plan to finally bring proportional representation to the US. But the dynamics of our dysfunctional single member district, first past the post electoral and political systems keep dragging everyone back into a two party system where the parties steal issues and dance around each other. Example... once the GOP was the party of fiscal "responsibility" until Reagan bought into Starve The beast. Clinton broke out of the debt trap and got us to a surplus only to have the GOP try and sabotage it at every turn. During the 2000 election Dems were for preserving that surplus. Come 2013 Obama decides to keep most of those irresponsible Bush tax cuts... and Dems cheer because he restores the top rate.

Perhaps in a true multiparty system parties could hold on to principles more than in our system.