The weather system WILL need some improvements - but I think it is not a priority now. Although, even in an unfinished game, eye-candy may come useful, to \"draw players\' attention away\" a bit from the other serious lacks.
Moving clouds would look fascinating (see newsky.zip in Crystal Space - it is possible) - if there are even clouds underground...
And in the future, the player should see when a storm is coming: dark clouds gathering, first thunder and lightning, only THEN should the raining begin.
Just a thought.
--
Greetings,
E.