Hi!
Does anyone know what are the best add-ons to make your sky/sun(set)/water/... look better? And where to get them? Thanks!

Thanks. I'll have a look. Is it any good? You don't sound very happy about it...

I fixed up my FS2002 water textures over a year ago and took some notes at the time.  I was then heavily into simming and had a pretty good handle on what I was doing, but by now I've forgotten the details, I do remember that it took a lot of "ya-gotta-be-wide-awake-for-this" texture file swapping.  The result was pretty neat, my water textures are a much better (blue-er) color, the shallows are light green, and all the water is also animated!  I also did the same thing to FS2004, but somehow cannot get the animation thing going there.  Here's the notes:

Main: Ponce (from FlightSim)
Water detail: Oceansfx>#7NW
Shallow: 37,38,43,44,49,50,55,56:Truthan-
re-formatted to 16 bit

I think this will all make sense if you find these downloads, they contain instructions within.

Look here, on avsim.com, and flightsim.com, use the search engines with key words 'Ponce', or 'Daniel Ponce', Oceansfx, and Truthan. 

My note:  "Shallow: 37, 38 etc." refers to the shallow water texture .bmp's that I guess I re-formatted to 16 bit for reasons I don't recall.  The water textures are located: Scenedb>World>Texture and are named: 044b2wa1.bmp, where 044 is the tex # (there's a whole bunch of them) and wa = water. 

Whatever you do, back up originals to temp folders first.

I did not notice any frame rate hit after doing this.