1. Great idea, but not currently a feature, and would require more than a simple snippet. I will take this upas a suggestion though and the developers will consider it for future versions. If you want to move it ahead you can create a customization, or look to GD Experts for help here: https://geodirectoryexperts.com/
2. Your best bet is to use one or more GD Locations elements on the location page. Set it for Enable location filter. Try creating one for country, one for region, and one for city.
[gd_locations what="country" per_page="20" pagi_t="1" pagi_info="before" show_current="1"]
[gd_locations what="region" per_page="20" pagi_t="1" pagi_info="before" show_current="1"]
[gd_locations what="city" per_page="20" pagi_t="1" pagi_info="before" show_current="1"]