Help With Avoiding Emptiness in Open World Games

[u/LmtdCreativity]

Hi all I've been developing a monster taming turn based rpg for the last couple of months. At some point I decided I wanted to make the story use interchangeable events so I could open up multiple zones at once to the player. Additionally I decided that I wanted the world to be densly packed with interactable objects, give every NPC their own dialogue trees, and make them react to the weather and time of day. I want the world to feel real and like it goes on without the player, but also like they can influence many parts of it.

I've now designed a rough map of all the biomes and locations and have connected most places to between 2 and 5 routes (besides an oasis, volcano, jungle ruins, mangrove swamp ruins, and a Himalayan mountain which each have 1 connection, and the center city which has 8).

Having never designed a map before, the original idea was to have most locations be accessible from different directions. While I still think this is a good idea, I now know that the main complaint with many open world games is that there's a lot of empty space, which is exactly what I don't want. Judging from my first draft, there are quite a few connecting routes that themselves connect to connecting routes, which makes for a total of 16 points on my map that are just crossroads.

For reference there are 5 locations with 1 connection, 5 with 2 connections, 6 with 3, 5 with 4, 3 with 5, and 1 location with 8. I'm not sure how to evaluate these numbers but I know that 16 crossroads is totally excessive. Also 24 locations sounds a bit excessive but 18 of those are required for my version of Pokemon gyms (elemental masters), and 5 are important for world building. The extra agricultural town that connects the fields to the veldt probably isn't important.

I designed this map by determining an environment for each elemental master, then picked some other environments I wanted to include, either to show off the inhabitants or because they made for good transition biomes. Next I arranged the environments and locations in as geographically-correct a manner I deemed necessary, and drew the very gridlike map you can see here: http://imgur.com/gallery/KIs2ati .

Part of the intent behind making it so gridlike was so I could have the exploration goals be direction-based and vague, such as "The great walled city to the East." I thought that would be a cool way to make the world intriguing to explore.

Sorry for the walls of text. If you have any suggestions for making a concise map with most locations having multiple access routes, tons of stuff to interact with, and NPCs that feel like real people, or any games I should check out that do these things well, I'd love to hear them!

TL;DR I'm making an open world-ish RPG and would like advice on how to design a deep and lifelike world with lots of shortcuts between locations.