Sorry, I'm still not seeing how a IPv4+ would be any less complicated (or as simple) as IPv6. In either case you would still have to:

* roll out new code everywhere

* enable the protocol on your routers

* get address block(s) assigned to you

* put those blocks into BGP

* enable the protocol on middleware boxes

* have translation boxes for new-protocol hosts talk to old-protocol-only hosts

* enable the protocol on end hosts

And just because you do it, does not mean anyone else would do in the same timeframe (or ever). You're back in the chicken-and-egg of whether servers/services do it first ("where are the clients?"), or end-devices ("where are the services?").