Abyssal Region biome

So imagine this you feeling like you've conquered the world, you got all the resources you'll ever need like all netherite and you feel unstoppable. but what if you add a new way to immerse the character in an adventure that fairs difficult for all users. you could raise land and water levels, and expand  the oceans downwards and making it darker the further you go. the old reminiscent creatures of the old Minecraft mob vote, the squid like creature that would drag you down. maybe increase its size though. then add a cool deep ocean ecosystem. a plant could be a cool weed that could refill your air bubbles  but it has a long cool down, so you have to go find another one. that could be a plant you acquire from the Sniffer. But even with the update aquatic, the oceans still seem bland, lifeless, and not a threat at all. If you read this please critique and tell  me your thoughts and maybe help me make more ideas for this pitch. thank you for listening Mojang!