You mean like the "Let's Get Started" option you have the ability to kickstart your hub with if you read everything at the end of the setup wizard? (What this does is install a few common built-in apps with "fake"/virtual devices so you can see what's possible. You can then use these apps for reference to set up new ones, swap out the virtual devices with real ones, remove any you don't want, or really just do whatever you want.)
But back to the issue, "built-in" just means that the app comes with the hub firmware. This is as opposed to custom/user apps that you have to install (as code) yourself. Similar with drivers. I think Hubitat Dashboard actually is installed by default, or was last time I used a brand-new hub, but it doesn't really do anything unless you configure it, anyway--nor would most apps, so I'm not sure how just having them "installed" is helpful (how would Groups and Scenes know what groups you want to create?). I'll agree that Dashboard isn't the friendliest. However, I think the Community is, so you should have good luck if you ask questions as they arise. I see you have some good advice above already, so I'll touch on one tip that I'm not sure I've seen addressed yet:
You can leave the width and height blank (they are not by default) for rows and/or columns, and they will automatically size to fit the width or height of your screen. This won't necessarily work for all screens; unlike ActionTiles or SharpTools, tiles won't wrap around to the next row but rather just resize in accordance with your specified number of columns and rows. (I actually prefer this behavior; I don't have to wonder how a screen of a slightly different size might wrap my tiles and mess up anything I wanted to be next to something else. I'm sure others prefer the other behavior instead.) But it works for most screens of similar sizes and saves you from needing to make a new Dashboard for each--but if you do want to do that, you can copy the JSON from one to a new one to get a head start.
I also wouldn't worry too much about Hubitat Dashboard changing so much that any of the community solutions you've found will stop working. The biggest change to Dashboard was about two years ago when Dashboard 2.0 came out (if you think the current Dashboards are awkward, I wish I could remember how legacy Dashboard worked...). I recall exactly zero changes since then except recent token/security changes that don't affect the Dashboards themselves beyond that, so you'll probably be good for a while. And if they make major changes, hopefully that's Dashboard 3.0 and you'll have the option to keep using these indefinitely.
Oh, and there also are third-party solutions--like SharpTools I mentioned above (actually pre-dates any version of Hubitat Dashboard), and ActionTiles is rumored to be coming soon. If you use iOS, you can also use an official HomeBridge integration and use that as your UI. I've actually come to rely less and less on Dashboards in Hubitat in favor of "real" automation instead (motion, presence, temperature, etc. drive things on their own), but it's still nice as one place to monitor things (e.g., lots of sensor states). I'm sure you'll find something that works for you. Good luck!