I'd really like to see weather in this game. Like when its cloudy or sunny, when you get a mood boost every few minutes. When it rains, it could reduce your mood every few minutes. Snow could leave behind snow piles which you could dig with a shovel for snowballs, and ice would leave ice on the ground which you could scrape to get icecubes.
Also there could be occasional "severe weather" events like tornadoes, which kill all the trees and leave lumps of earth on the street it hits and hurricanes, which floods all the underground areas in the region it hits. You could swim in there for a certain time and then you'd drown and die if you spent too long in there and can not enter the flooded regions for a certain amount of time. Sort of like the AL buff.
I know that some of these aren't good for glitchen, but they would certainly make the game more interesting.