Please no more Eureka!

[Reynhart]

Well then I ask it differently: Where is the big new battle endgame content for casual players in SB?

Let me reverse the question : If you consider that there's no battle content for casual players, what are Expert dungeons, normal trials, normal raids, and alliance raids ?

Also the relics were meant as an option for more casual players that didn’t necessarily savage raid.

The Relic in ARR was. Since HW, everyone has access to the Tome weapon without serious raiding. They also created wondrous tails to keep old content alive, removing the other purpose of the old relic. Once the two goals were covered, it was time to give the relic its own content.