I agree with everything said here, especially an early game recipe for bent wood, but we need to consider the varying workload all of these ideas might entail. I suggested the autoclave recipe because much like minetweaker it’s simple to slot in another recipe, that’s why I suggested omitting the creation of the new item steamed wood plank to make it simpler.
Drying wood in the sun and the addition of a raft would require new items, blocks, visual models and new or modified code. Then you need to consider the balance, how is the boat better than a raft? Would people build boats if it’s easier to build a raft? You also need to consider how the change might affect other mod balance (though I don’t think the boat is all that used in any mod).
Kerfing is good because it consists of a simple recipe addition but is inefficient which pushes the autoclave as the preferred choice in later game, however it should include glue, kerfing by itself wouldn’t create a rigid structure.