In the fourth episode of season eight, we have a wonderful scene where Bronn walks in unannounced, threatens the Lannister brothers, and extorts Highgarden from them. And yet, that's the extent of his work this season other than accepting the crossbow from Cersei in the premier and his jokes about brothels in the finale. In the past, Bronn has been a pivotal character saving Tyrion in his trial by combat at the Eyrie and convincing Jaime to help his brother escape King's Landing after the death of Joffrey.
Why not do more with this character? His scene with Jaime and Tyrion proves that a win from Team Daenerys gets Bronn a better deal, so why not have him turn on Cersei? After all, he is a sellsword.
In our version of this story, he'd return to King's Landing intent on killing the queen. If he succeeds, we have another spitfire of a showdown for the finale between Bronn and Jaime — which would be more satisfying one than the last-minute douchery of Euron's attempt at a fight. But more importantly, adding another name to Cersei's list of foes would build tension in the audience and make us wonder how she'll die. Will Arya get to her first? Will Brienne get to her first? Or will Bronn?