I am probably asking for a massive change in the architecture of NextGen Gallery.
NextGen Gallery, by many standards, is the best WP gallery out there. But the current architecture leaves a lot to be desired. Because NextGen Gallery still uses custom SQL tables, it does not play well with a host of up-to-date plugins...SEO, XML sitemaps, multilingual (WPML), breadcrumbs, etc.
Please update it to use custom post types, custom taxonomies, attachment post types, etc.