Relative to this extension request in progress: http://forum.simutrans.com/index.php?topic=9347.0
I've long wished for a two-dimensional click-drag land levelling tool. That is, click-and-drag from a corner (like raise/lower tool) and drag in two directions, and all corners are brought to that height, to level land. (sort of like you can click-drag now from the raise or lower tool and it will 'level' as you drag around, but individual points only)
This capability would also be useful for placing water to create lakes. And I know it can be done, since we have the forest tool! :)
Also, I apologize for putting in requests - especially two in one day. I know that I can't help accomplish any of them (at least, not yet), but at least I can clarify I'm not demanding. :)
I second this!