I hope Elon will update us on development on Raptor, carbon fiber tank construction and reuse efforts as they are still going to be relevant to any changed plans.

SpaceX might go for a fully reusable launcher able to launch just in excess of anything else past or present but less than BFR. No more than 150,000 kg to LEO but with a single stick. I think Falcon Heavy may be more complex and expensive than desired so I don't think it will be repeated.

Once you have full and rapid reusability much of the value of smaller launch vehicles is lost and it is cheaper to build and maintain a fleet of bigger vehicles than a mixture of big and small, and there is always the option of ride shares with stacked satellites. And once you crack orbital refuelling you can still do massive deep space payloads. Also it would be a good size for a post-SLS NASA and for cis-lunar which would be a good source of income.

I have no idea on upper stages or space ship. The challenge of reusing the Falcon 9 second stage and fairing, and landing a big spaceship on Mars might generate something new. Something that combines thermal protection, lift, some sort of control surfaces, retropropulsion and perhaps encapsulates payloads differently. Perhaps a payload bay that can be reconfigured as a tanker, space truck or manned exploration vehicle by switching a container/payload dispenser which would give a lot of flexibility. I like the idea of shipping some sort of containers to the moon or mars than can be cargo or habitats. You can standardise on handling and transporting them on Earth and elsewhere. But I am wary of repeating the mistakes of shuttle.