/agrees with
tiny lampe 
Also, the nice thing about
Natural Habitat is that you can install it separately, it works fine, and it doesn't conflict with
anything that I'm aware of. Certainly not with
All Natural, or
Enhanced Weather either.
Regarding
All Natural, it can do one of the other things that
Natural Environments did too - that is, you can have it adjust "colour moods", according to weather, etc. It actually does a lot more than that, especially if you maka use of (i.e., edit) the ini.

Plus,
All Natural actually includes all the weather types from
Enhanced Weather,
Natural Weather, and
Atmospheric Weather System - and you can mix 'n match from those types as you like. The other things it does, straight away without any editing, is add Real Lights (more realistic lighting) and Natural Interiors, so stuff like looking out windows and seeing stuff you actually might expect to.
You *need* http://obse.silverlock.org/ and http://tesnexus.com/downloads/file.php?id=22368 in order to make the mod work, is the only "downside". But these are great things to have anyway, I think you'll find.

The http://tesnexus.com/downloads/file.php?id=35230 would be your best bet, to get started with that incredibly useful mod tool.
A couple of other mods I like to add to
All Natural are http://tesnexus.com/downloads/file.php?id=35099 for darker dungeons and such, and http://tesnexus.com/downloads/file.php?id=34199 for looking out windows and *really* seeing the stuff you'd expect to - the next level of that, basically.
As for
Natural Vegetation, try http://tesnexus.com/downloads/file.php?id=23783 instead - a better version of the same thing.
And that's it - everything from
Natural Environments covered, and then some. :yes:
Enjoy!