@mrstevie18 (Snr. Design Director at Hasbro for SW) on Instagram posted this: "...the rear bay can fit multiple vehicles — some we might not even be able to talk about yet" ... now, next year is all about the Battle of Geonisis (it replaces this year's Return To Tatooine theme), so we can expect a lot of tie-ins to this centerpiece vehicle. Now, what vehicles (plural!) could he possibly be talking about that interact with the Gunship? Our money is on a BARC speeder and an AT-RT vehicle, those are the ones we see in the Clone Wars animated series interact with the Republic Gunships, and they both should be small enough to fit inside.
Meanwhile the backer numbers have climbed up to 2,600+, you have until September 8 to back it on the Hasbro Pulse website (it needs 8k backers to become a reality).