Actually gonna chime in with a different take where if you had to get rid of one of the three, I'd keep Iconoclast and the big Saheeli (assuming this is the Brother's War card?) and cut 3 mana Saheeli. Ideally you'd just keep all three in the cube, but if space is at a premium I prefer the options that have a bigger impact in the long run. Iconoclast is just more efficient and bigger Saheeli can just grind games effectively without running away with them (which is exactly where I like walkers to be).
I ran 3 mana Saheeli from release until my most recent cube update and it's always been alright, but 3 mana is a weird spot for a set-up card like that unless you can immediately cash in the body ala curve into Daretti, Scrap Savant
and Trash for Treasure
a legit creature. The -2 is great if you have a relevant target, but sometimes you just end up in the awkward spot where you can't really curve out correctly. Late game in a stall it's pretty sweet, but often times it's been a winmore option and otherwise middling to straight up ignored in my games over the years. YMMV depending on power level, but it's only been alright for me.
I'll probably bring it back at some point due to the hybrid flexibility, but as of right now Iconoclast has already done a better job at 1 mana cheaper for the primary function of making bodies and promoting proactive gameplay. It has slotted more easily into both spellslinger and artifact builds as most impact cards are at 3 mana, usually gets in for 2-4 damage over a game, and it's small enough that it can be dealt with rather easily.