Enworld is big. Enormous. The disc diameter is said to be 25,000 miles. Some recent adventures have corroborated this - some of the M-A teams have travelled for a month on phantom steeds, covering 8000 miles or more edgewards.
I've taken the liberty of superimposing three recognisable real-world areas on top of Halford's map, to get a sense of the scale.
The commonly used Orussus region map shows an area about equal to that of Mexico, or Saudi Arabia, to pick something more conveniently rectangular.
Obviously some of the placement on the Halford map is inaccurate - I have no idea where Monemvassia is, but I'm pretty sure it's not 5000 miles from Orussus. The Sairundan party travelled a little more than 3150 miles before they saw Helatia on the horizon. (It seems that many places that are said to be "in the Lands of..." are really not very close to the Towers).
What bothers me more than any inconsistencies in the known regions is the "blockiness" of the geographic features in the "new" regions. The whole of North America fits neatly inside the borders of one portion of the Lerrani Rainforest - it's probably 20 times bigger than the Amazon. There are hilly regions as big as the whole of Europe. "Lake" Ulek is 2/3 the size of the Atlantic!
Consider the geographic diversity of real world regions, like Europe, for example, or a small country like NZ, which is only 1/8 the size of the Orussus region (Australia, admittedly, is nothing but choking red dust and poisonous snakes for thousands of miles in all directions). There's room for there to be *anything* in any part of Enworld, though there'll presumably be less variation the closer you get to an Elemental Tower. I'd expect Enworld to have an inland sea or several. Maybe it does have a giant rain forest bigger than anything in the real world. But I don't see any reason why the map should look like a patchwork quilt of just a few squares. I'd assume "out there" is nearly as variable as the well-known central lands.