I don't have plans to include any more built-in (standard) mods.
Actually, I am thinking (for a longer time) about removing some of the currently available.
The default pack-in mods
should all either be nice and simple, or accommodate for pre-OpenXcom stuff like Util and Extender. There's no sense in overwhelming people either new to OXCE or to old X-Com in general with a whole battleshipload of second wave options right in the menu. (We already have a Skyranger full of them!)
Of course, if people want the old options that get axed, they could always be collated into one big modpack (one zip, multiple mod folders of course) and put onto the site. I volunteer in advance for my five seconds worth of troubleshooting, typing, and screenshotting to be shoved into any modpacks. I don't need kudos and credit for enabling a feature - thank the people who implemented it.