Righteous Glory is pretty absurd atm in combination with Cinderhulk... It also has a mega-short cooldown, unlike "Ye Olde Shrelias" which had a very meaningful CD.
i certainly feel that there is a strong justification for having 2 Righteous Glories per team (though not always).
Supports and Junglers saves ~350 gold compared to Randuins, which is nice, and it has a pretty forgiving path as well. Starting Coin is a good way for the Support to lose botlane, and it's nice to get the slot-efficient coin + randiuns effect + mana + health...
i think that it can be better than Aegis against high-poke teams since it gives you that initiation (AoE AP teams... Aegis is probably better since champs such as Amumu/Karthus/Kennen are really hard to avoid team damage). And, i dunno, i just feel like Randuins is a little weaker now than it has historically? Thornmail + Big HP item has seem to taken its place, since BT is such an uncommon item.
Not to mention, there is always the ... "Amumu Problem" where you hit that AMAZING flash, bandage, 5-man ult. But you're 2 screens away from all your damage. So it was all for naught
Righteous Glory helps fix that problem, and it's still relevant with 2 of them on your team. It also lets you "burn" 1 of them, wait 30 seconds, burn the 2nd, wait 30 seconds, use the 1st again... until you finally DO get that initiation.
It's also pretty weak on the "losing" or "turtling" team since the MS boost only works while running away (and the Randuins effect is pretty meh against a single tank), which is a nice change from "Ye Olde Shrelias" whose only counter was itself...