Does some type of lubricant need to be used for pump longevity with higher concentrations of the fuel
I've seen no need for additional lubricants. The fuel is 15% gasoline and I believe that provides enough lubrication. In the case of 100% methanol racing fuel it has almost no self lubricating ability so pumps will gall and seize if your running 100%.
I am running the Walbro 255 l/h pump and so far no sign of ANY problems.
I believe the "conventional wisdom" about how corrosive ethanol is, way off mark. As modern cars got certified to handle 10% ethanol blends, most all the early problems were eliminated. Even if there are some minor compatibility issues, they certainly are not major as I've got over 2 years of testing ethanol blends and the last year I've run almost exclusively E85, ranging from 50% to 100%.
I'm still running the stock fuel filter (never changed) at 48,000 miles so if there is any crap in the lines and tank, it is so small as to be meaningless in a real world sense.
When I do my next set of upgrades I will likely pull the fuel filter and examine it carefully looking for hints about what might be unhappy with the fuel. The fuel lines are steel so they should not have any issues at all. Some fuel tanks have internal coatings that degrade with long term exposure to high concentrations to ethanol. So far no sign of those sort of issues.
When I pull the fuel pump to get a close look at the inside of the fuel tank I am not expecting to find any significant problem. Even if there is, all you would need to do is take the tank down to an industrial plating house and have it nickel plated on the inside (same resistance to corrosion as stainless steel)