INI order should be consistent, currently it is not, especially when it comes to ActiveAccessExtensions.

AccessActiveExtensions is loaded in a loop, so that ini override dirs will be prepended in the following order with AccessActiveExtensions[]=ext1, AccessActiveExtensions[]=ext2 and siteaccess: eng
extension/ext1/setting/
extension/ext1/setting/siteaccess/eng/
extension/ext2/setting/
extension/ext3/setting/siteaccess/eng/

Suggest that settings are scoped so they always exist in this order:
override : settings/override
extensions: ActiveExtensions
siteaccess: normal & extension siteaccess
extensions: AccessActiveExtensions