Actually, the "natural" state of the earth is glacial
100 m lower sea level
huge continental shelves as arable plains
the northern lattitudes lost to ice sheets but huge tropical gains in real estate.
Indonesia would expand by about 10 times in surface area. Giant tropical rivers and forest plains. The world we see today is an illusion. A temporary thing... It's not "natural" it's the "Noah's Flood" world - for 10% of the time, the world is warm and sea level is high. for 90% of the time it is cold and sea level is low!
(if today's state were the long-term stable sea level, then the coastline would have built-out to near the continetal shelf-break. Many more flatland acres...)