I just posted this in a thread, but since I haven't seen the idea anywhere else, I figured it might make a good thread.
Now, I have not played the beta, and I probably wont, but from I have lurked through many of the topic here.
Anyways, here is the main idea I have.
What if you could only build a starbase inside your own culture? The could make for a few more strategies, especially using culture. (advent get a bit of an advantage but i'm sure something can be worked out) This would require research to be done in culture before you could even build a starbase. You would need media hubs, (or the other culture spreading buildings) to be built first, before having a starbase. This does make sense from a tecnhical standpoint because these are communication stations, and a starbase would probably require a fair bit of communication between other bases, planets and things like that. Also, the base could also possibly spread culture and your empire would slowly crawl outwards, allowing you to fortify with starbases as you go.
Like I've said, I haven't played it and I'm not totally sure about how the starbases work but I've seen a few complaints about building starbases in enemy territory or enemy gravity wells, which doesn't really make sense, why would you be building a starbase in enemy territory? This would prevent that, from happening and probably give room for some new strategies.
I don't really have any opinions of the starbases in terms of balance though, as I haven't played the expansion, but I figured why not put out this suggestion, the more the merrier right?