I think the autonomous probably won't become much more complicated than what it already is now... for the very simple reason that as the complexity increases so does the complexity of the testing requirements.
Not all teams are capable of building a full mockup field, for example. Nor do all teams manage to finish their robot with weeks to spare in order to test these autonomous programs.
I think the key in developing the autonomous area of the game is to keep the procedure relatively simple (not much more complicated than what it was this year) and increase it's strategic significance in the game. In last year's stack attack, had the potential to make the autonomous really worth while... but then the king of the hill came in and seemed to pretty much negate that. This year, again, you'd think knocking off (or grabbing) that 10 point ball would be worth more, but herding those balls (and managing to throw them in successfully) turned out sometimes to be less successful than just hanging from the bar.
(of course, there are always exceptions with those amazing robots)
I remember my adult mentor discussing this with someone else... (for the life of me I can't remember... it was probably with me
) if they wanted to make the autonomous more of a priority for teams to make it worth a set number of points. For example, rather than just having your score based on the final state of the field, if you had your robot knock off that 10 point ball, you'd automatically get 20 points for example.
Unfortunately, doing so would probably further unbalance the game. Where teams with the programming and testing resources would be able to develop a flawless system and teams where they can't afford to build testing fields or have time to test and debug the program... or even the experience and education to write the programs and work the miscellaneous sensors would be left in the dust.
So where does the future of autonomous lie?
Probably right where it is now; purely for a strategic importance. Getting your robot in place to climbe the stairs. Or knock off the 10 point ball. Something that would help you (or if you have bad luck, break you) but it isn't required by any means to have a successful match.