Maybe it's true that your preferred implementation would have been equally complicated to do. We can't know that not being privy to the process.
But you're wrong that the new implementation is something that TFP is still "planning to do". They already did it. Their implementation is not in the planning phase and they would have to redo it all yet again to do it the way you would rather see it done. Maybe they will if feedback grows as hot as it did back in August but I don't think it will. I think the fact that water can be gathered from sources using empty vessels will appease most of the discontent and the rest will be willing to use mods to get what they want.
Nothing they do will please everyone but with a lot of the adjustments coming in 2.5 that are direct solutions to player discontent about immersion (filling empty jars at water sources, seeing storms in other biomes from far away, having smell be a factor in zombies detecting players, using clothing to mitigate hot and cold climates, being able to go outside during storms without immediately taking damage, etc.-- I think most of the response will be positive.