Here’s a quick and dirty list (don’t look at it too closely, it’s too early to write proper regex 
):
foo@bar:~$ adb shell 'pm list packages -a -s | grep -v -e google -e android -e qualcomm -e qti -e tct -e t2m -e fp -e fairphone -e ims'
package:com.omusic.gPhone
package:com.gohappy.mobileapp
package:de.telekom.tsc
package:com.orange.update
package:com.fetself
package:com.fet.fridaywallet
package:net.fetnet.fetvod