So why isn't Colony the standard?
Colony predates me showing the game to RGG. It certainly could have been in the main set, and would have been if I had thought that always having Colony out was the way to go.
The game wants to be a good length in minutes, and a good length in turns. The 4 player game sacrifices turns for minutes; I don't know if that was the right move. Possibly there should be 16 Provinces for 4 players.
I liked the length of non-Colony games better and well that's that, that's why Colony isn't the standard.
People like to calculate the chance of having Colony given that you own everything, but remember that the rule scales Colony appearances to the individual. Some people do not have everything! If you just have 100 kingdom cards, a 4th of your experience is Prosperity and you see Colony a 4th of the time. It's just like how you see Peddler less often when you have more expansions. The expansions expand the game by providing new things that you sometimes see.
I know there are people who always play with Colony and man I don't mind. You can always have a Village too if you want, or always have Moat in games with attacks. I set it up how I like it but what actually happens is up to you.