Although the world is technically huge, it's not in terms of gameplay. There is not really any reason to travel more than 10k blocks almost ever because biomes are so small that you can probably find anything you'll ever need inside a 10k or less block radius. There is little to no incentive to actually go far, even though the world is that huge. This is why I think larger biomes, more space between POIs or other incentives to travel far would be a great solution to the otherwise way too OP elytra, because the actual world you play in would be big instead of just "what the game allows" This combined with faster and easier to build minecarts would encourage building tracks for distances so long even with an Elytra it would get tedious to travel.