I am a legal permanent resident planning on becoming a naturalized citizen of the U.S. next year and I want to file an I-130 petition on behalf of my spouse, but I recognized that he will have to wait more than four years before he can file for an AOS petition. Are there any benefits in waiting until the naturalization?
There is no advantage in waiting until the next year. You can file the I-130 now and as a citizen you can get an upgrade on your I-130.