2001 225HO

I am getting the boat serviced from its long winter nap and have about 300 hours on the motor. What are some things that should be checked, changed or serviced other than the normal routine stuff ?

Here are some things I am going to ask to be done, new plugs/ indexed,
water pump impeller/housing if needed, water separater/ filter, a Decarb, propshaft lube & torqued, Steering component inspection, I know there is an Exhaust sensor somewhere? Anything else that often gets overlooked ? Thanks