Fixing "Brad", Going Forward, part two

Continuing on from here, let's start with some ground rules:

Rule One: No retcons. While scenes from the movie can be fixed to plug/cover plot-holes, the net effect of each scene stays the same.

Rule Two: What you saw is what you get. The movie couldn't have shown every moment shared between Twilight and Flash... but they showed all the important ones, and they didn't skip over any kind of long discussion of life, future plans, etc.

Okay? Okay. Onto the step-by-step plan.

Step One: Don't start anything before... oh, the midpoint of season 6.

Step Two: Don't build any kind of lasting relationship between Twilight Sparkle and Pony!Flash. They have no shared history, and nothing in common. That Flash would be too intimidated by the tiara of the princess to get to know the pony wearing it.
THAT SAID, there IS room for a few entertaining episodes involving Pony!Flash, possibly focused on how hilariously doomed any such relationship would be.
"Hello! I know we've never met but you remind me a HUGE amount of this guy I knew for about three days and we kept bumping into each other and he helped me out and we danced and I think I liked him and I think he liked me, and on this basis I'd like you to be my colt-friend!"
Seriously. If that line doesn't bring to mind Lesson Zero levels of zany madness Twilight Sparkle hijinks, then why are you here?

Step Three: Halfway through the sixth season, have the changelings attack the Crystal Empire. While Celestia and Twilight Sparkle are confronting Queen Chrissy in her lair, the rest of the cast beat off the invasion. But as the dust settles, it turns out they've got an extra Flash Sentry, one babbling an insane story...

If you're with me this far, I think you can guess what's going on. But if TwilightXFlash is going to become canon, and be done RIGHT, then I think it needs to be Human!Flash. But why would he have decided to leave his world to follow a girl he only knew for three days? Well, that'll be in Part Three