The suggestion marks a shift from two years ago when Shell said adding Urals would not be "worth the trouble".
The benchmark, based on light North Sea crude grades, is used to price about two-thirds of the world's oil but a decline in North Sea output has led to concerns that physical volumes could become too thin and prone to large price swings.
Platts announced it would add a fifth grade, Troll, to the benchmark slate from January 2018 but Shell says more must be added in the next two to three years and considers Russian medium sour Urals as a top candidate.
The benchmark is now made up of Brent, Forties, Oseberg, and Ekofisk, known as BFOE.
"A good benchmark need not only be representative of what the region produces ... If you had to pick one grade of crude, Urals is the one which northwest European refineries should be designed to run optimally," Mike Muller, vice president of crude trading and supply at Shell, told the Platts Crude Summit in London.
Muller also suggested the price of dated Brent be derived from the average price of a basket of crudes, rather than by using the lowest priced of the four BFOE crudes on any given day. This would simplify the price-setting process, he said.
Two years ago, Muller said European refineries were already free to buy Urals - a crude stream that dwarfs North Sea streams in volume - as a substitute to the North Sea Forties grades as they are similar in quality.
Muller also called for the formation of a committee of independent experts to consult with Platts and the wider industry on future changes to the benchmark in order to ensure the views of all market players were represented.
Shell is one of the world's largest crude traders and one of the most active players in both the North Sea and Urals markets.
Shell’s North Sea production is set to drop by more than half to about 110,000 barrels per day after the sale of a large package of North Sea assets to private equity-backed Chrysaor last year. But Shell will market Chrysaor’s volumes for several more years.
(Reporting by Julia Payne and Amanda Cooper; Editing by Jason Neely and Edmund Blair)