So, in my teaching campaign to my kids and niece & nephew, they want a magical horse-drawn caravan as a mobile home base. Think a two (compact) story RV. If anyoen saw the animated Tangled series, like what they have in the second season. My nephew actually built a prototype in Minecraft.
My old-school practical thoughts are like "it's damn unwieldy" and "it's go up to fireballs" and "what happens if their horses get killed far from civilization and they need to abandon it" and "think of all the terrains they can't go on".
But the flip side of player investment and their joy in something fantastical makes me willing to give it a go. They are currently in the feywilds - one of the characters is an eladrin, and another is a half elf searching for her mother with a clue that if not her mom then maybe her grandmother was from the feywild - and it seems like just the thing to come from there that I can't hand-wave away problems and make it magical (in the real sense, not the game term, though it would be that as well).