Welcome to Librarium Online!
When I started BA I thought that many other BA players would have the same list as me(close combat ripping marines) but I was wrong, they vary alot!
So in your opinion what should a BA list look like?
It should look like whatever you want to play. Some people like a lot of Rhino mounted tactical squads. Others prefer a foot slogging infantry with no transports. It all depends. That's the whole reason for having multiple choices, so each person can make the army they want. If you want some examples of different lists just look through the Army List forum.