This pair is great at saving your stuff
This was the only land I decided to add to the list under those criteria
The secret is its Eminence ability, which reduces the cost of your other Dragon spells by one mana, even while The Ur-Dragon is in the command zone
While this doesnt immediately sound useful, the inclusion of characters with enters play and exits play abilities means you can multiply the uses you get out of each card
Likewise, if your opponents are playing decks focused on synergy / Combo, you might not be able to take advantage of the cards you get from them as well as they can
Some of it is no doubt due to homogenization and tools like EDHRec, some to the expansive and varied content created by the excellent community, and some to the natural evolution of playgroups and card pools over time