Alcohol, Skooma, and Moon Sugar are all very well and good. They add atmosphere to TES. But I'd like to see them do more than just affect stats and be there for for atmosphere. GTA4 of course had the best, or at least most realistic, simulation of being very very drunk. Better living through chems was a great mod for FO3 that actually added visual effects to the chems. I'd love to have the world be a hard edged, pulsating thing with a lot of glare (or whatever you imagine) for skooma. Moon sugar could make things colorful and add a ton of motion blur.
As for diseases, again in the past they have just been a minor stats inconvenience. Something like Far Cry 2 would be a lot more interesting. With your screen occasionally going blurry and hard to see, progressing to a racking cough where you can attack, and finally attacks that completely debilitate you. Wracking coughs as your characters is brought to his knees. If diseases are going to be in, and I hope they are, have them add something very tangible to gameplay.
As for diseases, again in the past they have just been a minor stats inconvenience. Something like Far Cry 2 would be a lot more interesting. With your screen occasionally going blurry and hard to see, progressing to a racking cough where you can attack, and finally attacks that completely debilitate you. Wracking coughs as your characters is brought to his knees. If diseases are going to be in, and I hope they are, have them add something very tangible to gameplay.
I'd also like to see them implement an addiction system. Skooma in TES is supposed to be addictive, but I never get that feeling when I play around with it.