Personally I enjoyed and am continuing to enjoy Eureka. I'm really happy with the content and should have my 4th weapon in a day or two. I'm not alone I'm sure but be that as it may people wanted more than running boring old content ad nauseum and they designed this content around relic and I'm thankful they did. The didn't add the relic to Diadem they added it to Eureka and relic wasn't added as a stick it was incorporated as a part of the design for obtaining it that was new.
Relative to whether or not it'll be playable in 5.0 I suspect it will be. They'll nerf it so it can be solo'd or played with very few people in zone in my view just like they nerfed the old relics into oblivion making them super easy to get.
Haters love to slap the Diadem label on the content but it's not Diadem.
