I wonder if Brock loses title to Lashley, but still wins the Rumble. lol
Think it's more likely then you would think.
I thought Seth was going to win it but he is busy now. Big E could win it, but I don't think it's farfetched to have The Bloodline or Heyman cost Brock the title (Heyman could even do it "accidently") and then he enters at 30, wins, and challenges Roman (Heyman pulled strings or something)
They could go the other way and have Seth beat Roman and Brock beats Lasher and they swap the belts between brands. Though I have no idea who would challenge Seth. Maybe KO or E. And don't know why wins the Rumble, maybe E or KO, or hell maybe Roman wins it in that situation.
I don't buy they ever had plans for Roman to drop the belt and chase into Mania though.
I would bet money Heyman plays into the finish of at least one of the title matches.
I don't have a clue who wins the women's match. I could see all of Rhea, Sasha (if healthy), Bianca, or Bliss winning. I assume Asuka will be one of the big surprise returns and honestly should could win it too. I don't think Bayley will be healed in time to be a surprise return but on the off chance she is, she absolutely could win it too.