Honestly, while I don't like that Natasha didn't get the same farewell Tony did, I understand the route they took.
Opening the movie with Clint losing his family so dramatically helped set up the story with a quick and heartbreaking reminder of just what people lost in Infinity War. I love that opening. To not give that opening true closure-- to not let Hawkeye have a significant role in the final climactic fight-- would be hard to take.
Further, setting up a Soul Stone sacrifice within the core team that would have an equal emotional pull to Thanos sacrificing his daughter was nearly impossible. The only other ones I can think of would be Cap and Tony (though they basically have to be there at the end or the fans riot) or Bruce and Natasha. But I think having Clint and Natasha have to decide who's sacrificed, after setting up their long-standing friendship from the first Avengers movie, was the best move.
So from there, if you combine those two assertions-- assuming you'd agree to either-- Natasha is basically the best one to die for the Soul Stone. There should have been more weight to her sacrifice, but the actual decision by the writers to let her die there doesn't bother me.