I would like to see them provide some form of deployment shenanigans honestly. Such as being able to be replaced with another unit leader later on. At the very least it should have the same kind of deployment as Jyn, and potentially allow for a wider radius of Infiltrate denial.

Infiltrate seems like a given at this point. I could see a boat load of different purposes. Infiltrate and comms jammer could do some damage to an opponents first turn.

I think it would be most fun to have a very customizable model, in the sense that it could take on a communications role, support role, or a combat role. Even better if they throw in AOE damage when destroyed or have the self destruct as an option.

Perhaps it could act like a "long range comlink" for any model within R1 of it.

I wouldn't be surprised if they are generic operatives. At least in ESB, they operate as solo units. Command cards or ways to improve command cards could be a blast.

Not that it means anything, but we do have a probe droid on the 1 pip generic command card. Maybe something to do with looking at hands? "When your command card looks at your opponents hand, reveal another card?"
OR

Your command cards when initiative when tied - sorta like Krennics ability.

I have high hopes that Probe droids are the next announced model for the Empire, if not more bounty hunters.