Depending on the prevalance of Dispel in Limbo (though from what I have seen/heard so far, I'm guessing this immunity will be 'required' on any self-buffing tanks), it would be nice to have an Immunity option that doesn't totally nerf a ring-slot or require godly randomization (*cough* Raj *cough*).
XR Mord/Breach rings currently provide (pre-randomization) 15% Elements/5% Exotics, with one Exotic being bumped to 30%.
So for a Set Ring covering the forms of Dispel Magic, something like 15% Elements and 10% Exotics would be reasonable, considering this is a Paragon item and there is no option for randomization/augmentation. Possibly a tad over-ambitious, but 12% Elements/7% Exotics would be the bare minimum IMO.
Edit: Replacing the original idea with Woku/Raj's suggestion, as per comments. Thanks all for feedback!
That works too (personally I prefer yours). I did consider Esoteric% as well, but thought I would stay more in line with existing XR rings to start with. AFAIK there are no other rings covering all Esoterics (apart from Vestige), so wasn't sure if it was over the top since Dispel is considered 'rarer' than Mord/Breach anyway.
I would first compare the actual BUR -> XR ring planned upgrade (let ignore randomization on both endings): you gain 5% to all elements and 5% to all exotics.
The Abo dispel ring is actually top tier loot in the current module and provides exactly 0 immunities; I think any planned upgrade should stop at around the same power bump received by other immunity rings, so +5% elem/exo. Or something a bit more unique, like esoteric immunity capped quite low: XR rings cap it at +25% (the sum of the other immunities is comparable to the BUR versions), so a dispel ring with 5% vs all esoteric damage could work.
I'd still prefer seeing Dispel Imm added to other (very weak base) item slots (think at Lowbie Cleric Helmet), so that one of the hardest to get drops keeps its usefulness, and to have more gear options.
Will be hard to stack up esoteric immunity anyway with this; ring not covering ele/exo, and most of the XRs covering esoteric only cover that. So covering ele/exo will cause trouble if you wish to have incredible coverage of esoteric immunity with this; yet i feel if it gave something like 10 exo 15 elementals it would be too easy to cover exotic and elementals with this ring, even with the "bare minimum" of 7% exo 12% elementals. In particular making it over the top for pre-PL areas.
Edit: I also considered another item slot, but it is very hard to justify any of them. Perhaps a basically empty helmet would work - with some cosmetic fluff on top. This would make it contest amni immunity / other goodies, making it quite balanced option, but I wouldn't be able to say right now what the stats should be.
All good points, I guess I did underrate Dispel Immunity. Though I still feel that fair numbers are dependent on how prevalent Dispel is in Limbo compared to the current endgame (ie: how often most toons actually need to wear it). Anyway, I am happy with the suggestion of 5% Esoterics instead (edited OP).
Also keen on having the immunity placed on a weak item in a different slot, but I will leave that for someone else to suggest