Yeah I'm totally in Love with that sky texture and have been recolouring and using it as dark sky variants for every doom sky I can think of. I like the sky to match how light or dark the map is so, for example TNT's map 21's outside area is pretty dark so instead of the bright red sky I use the original red version of the above sky from mechadons big box o skies pack. I feel it makes more sense visually and it's an excuse for more varied textures without totally breaking the theme of the mapset. I mean, it's still red right? Just darker. To match the map. This is also true of map 5 of tnt as well. As you may or may not know, In major crisis I've gone and created dedicated sky add-ons for doom doom2 tnt and Plutonia. The original idea for these was to fix short sky tiling issues in zdoom engine without using ugly engine sky stretching (not really an issue in gzdoom though but I like backwards compatibility and actually prefer zdoom engine so...meh) but I've since expanded on it to include not only standard but also darker variants of most skies (and any mountains etc) for those maps that are darker and therefore look a little odd with really bright skies... It's just a way of adding a bit more life to those old maps we know so well without changing too much to make it visually jarring. Quite a tricky line to walk. Easy to go too far. Great if you get it right though...

*edit*
at it again. thanks to permanoob ive learnt to do some nice effects and recolours by porting colourschemes from one graphic into another to theme the sky textures with much less effort.
so time to re-assess those tnt 'episode one' skies methinks

standard:
sky0a_.png
dark version (intended for map05):
sky1_dark.png
*edit2*
oh and a new version of this'un for doom2 'episode1' sky:
doom2_sky1_new.PNG
feel free to use of course
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