You’d have to ask Ragan and Grembel about how less janky it might be now. I joined in around the last DLC, Aberration. So I’ve only seen what they have now.
Each DLC is both a huge new map along with completely new scenery, some new gameplay elements, some new dinos, boss(es), etc. So this expansion is the continuation of a long story, a lot of which I don’t know much about. The gameplay will be familiar, the map and perhaps some of the dinos you remember might not be there.
Then entire cluster is PvE, so really, jankiness is minimalized without fear of meshing and the crap that comes with PvP. Personally after playing Conan Exiles for a bit with Trip, I find ARK a -ton- less buggy and janky.
The cluster is Steam (PC) setup. The servers on the cluster are modded, so when you log in the mods will auto-download and install from the Steam workshop. Since several of the mods are large, you may have to attempt re-connection a few times before everything will download completely. The cluster itself is multiple maps/dlcs, and you can transport between them with your player, dinos and gear.
The map DLCs require that DLC purchase, or the season pass (all DLC’s.) The non-DLC maps just require you to go to the steam page and subscribe to that free map content for it to kick off a download.
The Island - The very first base game map, it has quite a bit to it
The Center - A free map download, it has the same dinos and types of areas as The Island but in a completely different design.
Scorched Earth - A DLC, new dinos, this one is on an extreme planet plagued by heat.
Ragnarok - A free map download, it takes a little from The Island, and some from Scorched Earth and presents as an all-in-one that is one of the biggest maps.
Aberration - A DLC, new dinos, this one is another extreme planet plagued by radiation.
Extinction - DLC map, new dinos, a futuristic tech infused world with new dinos as well as mechs and drones.
The connection password for all servers is the same: