Trying to decide on rim width. What are the advantages/disadvantages for going with the smallest or largest rim size for a given tire size.

For example, a 275/40-18 tire has a recommended range of 9-11". Obviously the 9" will weigh less, but are there any disadvantages to this?

My ultimate tire size combo is going to be 245 or 255/40-18 front and 275/40-18 rear,. If I get 18x8 and 18x9 I can also use the stock tires until they wear out. My other choice is 18x9 and 18x10. If I go with the narrower ones, will I regret it for some reason later? This will be my 2nd set of aftermarket wheels, and I want to get it perfect this time. (Iforged 2pc aeros)