I completely disagree that Disney will go this direction. They haven't made any attempts to hype up that this will be a main feature of the land and as Potter has proved, if you have a good enough product and a strong enough brand, you don't need to dilute it down by throwing poorly cast look-a-likes everywhere.Let’s agree to disagree. And wait for the legacy characters to appear after a year or two.
If they do end up going the character route, firstly they need to cast absolutely with perfection. Also, I could see a Poe meeting alongside BB-8. Especially if they're going to stick with the immobile BB-8... it's kind of awkward doing a M&G with BB-8 right now whereas Poe could add some life to that M&G.Here's one option: Stagger the characters throughout the day based on the 3x3 movies. You can spread it out all day: Anakin and Obi-Wan and Maul in the morning; Vader, Luke, Leia in the afternoon; Rey, BB-8, Kylo in the evening. Or, rotate through the timeline a few times through the day.
No overlap of timelines. The full gamut of characters. Show up at the time that your favorite trilogy is 'current.'