So many flashbacks in this series are going to have this same problem. Especially Enyes Lobby. Did the other strawhats actually learn any of those secrets reveled revealed in those episodes? There's a lot of "this could be really bad for the entire world" things that show up in Robin's and Franky's backstories the others really should know.

Should be smooth sailing after this arc to Alabasta... damn, I hate Alabasta arc...

It's still going to take a while to get there. Next up should be Loguetown, then possibly Warship Island(if he does filler arcs), then Reverse Mountain, Whiskey Peak, Little Garden, Drum Island, and then finally Alabasta. There's also the two side story arcs as well, but since they don't feature the Strawhats the author might not want to do them.

So another 12 years then?

One of them had Coby and Cory plated Coby

There's a gag in One Punch Man about that. It shows what a flashback looks like from outside.

pretty sure robin actually DOES say at least some of the stuff in her flashback, she tells Spandam what the golden den-den mushi does at least