I moved your question here (I know the underlying forum note says post your question regarding BotE here but I do think, questions about in-game handling are best posted in the general chat
).
as for the answer, you can mod starbases to have way better hulls with the editor. in the official release though, there's a recent idea of the team that one could "design" outposts and starbases just like with the ships to have them have better hulls and stuff for the price of longer construction time.
also minefields around starbases are strongly considered to be rendered possible by adding it to the special ship design. let's see how that develops..