Tick tock Imu stans your man will be facing the grim reaper that is Blackbeard soon. But don't worry Blackbeard coming for everyone whether it's Imu, Rocks, Roger, Shanks, Akainu or even Davy Jones and Joyboy.
Oda literally told you in chapter 957 what's in store for Eos Blackbeard and Eos Blackbeard pirate. That chapter wasn't setting up the Rocks pirates whether it's Blackbeard father himself or Big Mom and Kaido. In fact those 3 are precursor to what Blackbeard will accomplish at Eos. Let's start with Rocks himself Blackbeard will destroy the Marines, bring down the HolyLand with the Celestial Dragons kill Imu take his powers and become King of the World. And he'll do what both Kaido and Big Mom acquire the Ancient Weapons also obtain the One Piece and also become Pirate King.
Blackbeard will make what Sengoku said in ch. 957 a reality when he creates the strongest force this world has ever seen and surpass Roger bounty. And also put the Celestial Dragons in mortal danger forcing the future Pirate King and Hero of the Marines Luffy/Coby to team up to stop him.
Oda set up Blackbeard getting the pieces in place to accomplish these goals during the Egghead arc. 1st it was kidnapping Pudding to take him to Laughtale, defeating Law to acquire the Road Poneglyphs, his crew capturing Garp and of course sending Augur/Devon to Egghead. Where they touch Saturn which will allow Blackbeard to gain control of the Seraphim and also pick up Caribou who has information on 2 Ancient Weapons.