The idea of only bringing out the WWE Championship when Brock wanted to is a fantastic gimmick, and builds prestige for the title.
You get 2 or 3 shots at it in 4 - 6 months, how is that bad for it's image? It wouldn't work all the time but if you have a fit Bryan or Rollins or Reigns or whoever who can hold it and come out Raw after Raw then the angle isn't going to work. For Lesnar it's perfect. It's also a massive push for whoever does eventually beat him and take it.
My ideal next few months would be:
Bryan comes back and turns heel, Ziggler also turns heel and they become allies.
Reigns fueds with Wyatt or someone else and fades out of the main event scene.
Rollins turns on the Authority and drops J&J, turns into the anti hero everyone is desperately hoping Ambrose turns into and is pushed for the Title against Lesnar at Mania.
Ideally, I'd like a Bryan, Lesnar, Rollins Triple Threat for the title at Mania, where Rollins is the only face, Bryan wins in an epic match of back and forth between the 3 and as he's celebrating, Rollins cashes in and jumps off the rafters into a stinger splash and reveals himself to be Sting 2.0
Then him and sting take over the entire WWE.
(I think I lost my train of thought there at the end).