I think there should be an update exclusively dedicated to rivers. Currently rivers are often an annoyance and are rarely useful without tedious canal work

• Better river placement : Rivers should flow as they do in real life - starting from their source in a mountain and emptying out into the sea.

• Flowing rivers : Rivers should have gradually decreasing heights. [edit] Waterfalls could happen in cliffs (for instance in a mesa biome).

• River boats : In order for boats to be able to navigate upstream despite the height differences, there could be a new type of boat that can sail upstream but will break in deeper waters ; this would be more of a feature for a mod than one for vanilla MC, so perhaps just make boats sail upstream.

• More river sizes : Rivers are about 5 or 10 blocks wide. However IRL rivers can often be much wider than this. It would be nice to have some bigger rivers and larger estuaries.

• Less dried-up river beds : These happen a lot and are really annoying if you want to sail up a river. There could be dried-up river beds in the savanna or the desert, as a feature, but random breaks in the river should be done away with.

• Flood plains : There could be shallow marshy lakes on desert rivers.

• River mobs : There could be actual fish mobs in rivers ; or perhaps river dolphins, which would occur in larger rivers flowing through jungles. There could also be grizzly bears in rivers or streams flowing in colder biomes (if fish mobs were implemented, the grizzlies could target them).