I totally endorse restrictions. No pink flamingoes, no blue gazing balls, etc.!
My house in St. Louis was on a private street (which essentially meant we had gates at both ends and a non-interfering "association," plus expenses the city wouldn't cover) and it has been so since the mid-1930s when my father-in-law spearheaded its status.
Very, very loose restrictions existed, but, Boy! Do something someone objected to, and the acrimonious discussions could go on and on and on, sometimes even for years!
In the long run, the only people who really violated the "rules" were short-term owners. They moved away when the rest of us became "too unfriendly!"
SWR