Less overall maps, but a few updated and possibly bigger ones
Helbreath as a game was originally planned to support around 600-800 ACTIVE players. Currently the game peaks around 200 active players (probably not even that).
The game has way too many maps for the active playerbase, which kills the game. 95% Of the time its a single player game outside of town unless you have co-ordinated action with other players, thats not what an MMO is supposed to feel like.
We should have way less maps than we currently have, but at the same time adding new or updating old maps would be great new content. Maps should also have more interest points within them. Boring and one dimensional map designs like SW, DV and D3 should be removed and repurposed.
Off the top of my head I would suggest only having one or two TOH -maps, but creating more interest points within (pits, spawn points and so on).
I would do the same with dungeons, only a maximum of 2 dungeons is needed. D3 is a massive map that serves no purpose in the game, it is also poorly designed and basically nothing but lava, you could easily redesign it to serve the purpose of both D3 and D4.
I would also completely get rid of Silent Woods and Death Valley and repurpose Eternal Field and Rocky Highland to serve a similar purpose to those. Currently EF and RH are just waste of time that you have to travel trough while going to more interesting places.
Middleland Mine is a useless map, we could simply get rid of MLM and have mining spots withing the rocky parts of ML and make that map more alive and action packed.
You could update some of the maps and make them a little bigger. That way we would have new content and while we wouldnt lose that much overall map space, we would have more action within the fewer maps. Having fewer bigger maps also help make the game feel more immersive and less instanced.
Towns could also be smaller. 60% of the town maps are unused waste of space that are only there so you get annoyed while having to travel for long distances. It makes no sense that a TOWN is as almost big as MIDDLE LAND.
None of this makes any sense. What you're proposing would go against the goals you're setting.