Easy to Develop End Game Content

There is a lot of discussion and ideas around endgame content on Reddit. Great ideas that I hope the dev team is working on. Some of them require a lot of dev time but will be well worth it. What are some ideas for end game that won’t require too much work? If end game content isn’t available I’m afraid we are going to lose more ppl as more ppl get to that end game waiting room.

An idea I had was to select one boss a month to put at onyxia lvl of difficultly. You get 1 month to figure out the fight and get rewards. You can put phases into the fight and even give rewards based on getting past a phase. That way the lower lvl rewards might be obtainable for mid game users.

Ex) phase 1 = 500g Phase 2 = Rare-O-Matic Phase 3 = 500 valor

Any thoughts you guys have?