RNG finally decided to help me out. In the last couple of days I acquired an Unstable Anomaly, Focus + Restraint, Delsere's Shame, Blood Bracers, and a Crown of the Primus. Plus some miscellaneous other - the Halo of Arlyse and Convention of Elements are probably the more relevant ones. Feeling a lot better about the build now; exploding T9 monsters with ease, although it feels slightly squishy still at that point (..although I sometimes mentally define 'squishy' as 'can't survive standing in the middle of an exploding Molten pack', so maybe that just means I need to push a bit more aggressively.) Haven't spent much time with the Blood Bracers, tho, so I'll see how the bonus shield works out. Should try out the Halo with Ice Armor next if I'm still feeling like there's not enough Toughness.