As building becomes more important, it might actually be reasonable to make a way to remove water tiles (and, maybe, other), because they prevent from building large and convenient structures.
E.g. by building walkable and buildable "bridges". If such bridges would be semi-transparent (as desert bridges), it might be even fun to build a house over water (and even using it to fish or to drink) - I always preferred such homes in Minecraft :).
The game already has a way to remove water. You can use heat sources (eg heated stone or flames cast by a spell) to vaporise it. A low water tile needs two hot neighbors while deep water needs three. But you have to be a bit carefull if you use heat sources because trees can catch fire because of them.
It would also be easy to add buckets that work like in minecraft but I'm not sure about this feature. People already call rba a minecraft-clone..
Bridges and platformes sound like a cool idea to me. Maybe there should be wood bridges for water and stone bridges for lava.
I just added buckets as an experimental feature. Please let me know what you are thinking.