I'm going to disagree with moving the main tab - but that is my preference I guess.
The simplest way to re-order tabs that are scafollded is to change the order they are defined in the has_one/has_many/many_many.
Other than that I'd remove the tab and then add it again in the order I'd like.
I think I have tried the re-order and it didn't work out for me.
But i can actually not change the order they are defined. Main and metadata are populated by the databjects-as-pages-module, adress is populated by the the adressable-module. The rest is by my own scaffolding.
It was a wish of my client (a little bit oldfashioned guy) to rename the main tab. i guess have to 'advice' him to leave it well alone.
For the order I'll give the remove/add-thing a try.