Well, allow me to go a little bit off-topic, but this build is designed and destined to be a high pushing build. And a superb one. It is not very optimal for lower content (aka Normal rifts, T16, bounties, speed Grs). You made some alterations and gave more emphasis on speed and there is nothing wrong with that but wouldn’t you prefer to play a speed build that has 3 times the speed of this and still can one shot the entire screen if you are not pushing?? I know that i will do that in the next season and have this build only for pushing. Anyway, that is your choice alone, you should play it however you like it. But overall for that content i believe bane of the trapped is still of some value. Also if you are doing bounties with groups, unity pretty much becomes worthless cause there is no one to share the damage with.
Andariels Visage is a pretty good choice for helmet even for pushing so that was a good call. Make sure you get poison damage there as well. It can be even more important than the socket in very high GR. Nemesis are also amazing in slot even for pushing cause if you are almost at 99% of the rift you can just leave one pylon after the boss spawns. You will first stack a few strickens on the boss and after a while you are gonna activate the pylon and spawn some extra enemies. If you group them up the area damage will come into the equation and you are gonna kill the boss faster. Overall it will give you faster progress inside the rift. But ancient parthans work well too.
The stone gauntlents - ice climbers combo will make you a beast if toughness is needed. For pushing i would never take them off. As you probably noticed, this is a super tanky build (thankfully) and you can imagine on high pushes having this damage mitigation, on top of everything else, will make you a monster. At some poing you are gonna have to make a decision. You can probably cube the illusory boots to get on top of monsters if you chose to wear depth diggers. Or if you want to wear golemskin breeches to get extra toughness you have to cube depth diggers. Both options work fine.
For this kind of choices usually there is no simple answer. You have to make the adjustments as you see fit, cause you are the one playing it and you alone can know what is this small detail that you are missing. Is it a bit of damage? Is it a bit of toughness? Does not being able to walk through enemies cost you deaths?
To answer your question directly, in your place, i would chose bane of the stricken.
(Note: This build is not a natural Rift Guardian killer like Crusader, or DH impaler so stricken is probably even more essential here)