Franklin County & Pataskala (in Licking Co) are not going to give up any state mileage to sort out a numbering issue out near Granville.
Unless someone(s) want to payoff ODOT....
I was just learning about the Avenue of the Saints, the route from St. Louis to St. Paul. I have driven much of it before, but I didn't realize it was supposed to be a highway to connect the two cities. Because of the mishmash of numbers it carried (US 218 and US 18 among others), Iowa gave it a consistent number, Iowa 27. It is also known as Missouri 27 for much of the road in that state.
ODOT gave SR 32 its number to bring consistency to the corridor. Originally, it was SR 32 (SR 74 prior to Interstate renumbering), briefly SR 772 (?), then SR 124, SR 346, and US 50 to the West Virginia line. The SR 32 designation was eventually extended east overlapping SR 124 and replacing SR 346, and then later SR 32 was also multiplexed with US 50 east of Athens to provide a consistent designation for the corridor.
I agree that the numbering on the Columbus-to-Newark corridor is confusing. At the very least, ODOT should extend SR 161 east to meet SR 16. I could see maybe replacing SR 16 with SR 161 east to Coshocton but I don't know there is an appetite for that renumbering. You still have the corridor east of there continuing as US 36, US 250, and US 22 over to Steubenville, and I don't see a state route getting extended over that.