The magic mushroom current effect is lame. They have good effects in the game that work for magic mushrooms. The hyper color shift and wavy distortion combined together would work well for shrooms. The only things that are missing is making the models size grow larger and smaller relative to distance, maybe have some objects randomly render as others.
Alcohol should be a simple blur and hemp should be a haze.
Really, Jorb and Loftar need to take a day for inspiration and go into the woods and eat 4 grams of mushrooms each. Then they put whatever they saw in their trip into the game.
One can dream.