You forgot one...though it never made it to production, the prototypes WERE converted from other airframes;
Major structural changes too. 56" longer, 2-2.5 tonnes heavier, removal of ventral fins... it actually has a lot in common with the Su-34 where the modifications are really comprehensive enough that it should get its own designation as a derivative design.
The XL is mentioned briefly in Red Eagles : America's secret MiGs as it and the F-15E prototype were given some brief evaluation against the 4477th's MiGs. The F-16XL had eye watering roll rates, but it was mentioned that it rapidly bled energy during sustained turning, which isn't that surprising, since that's a common observation of tailless delta designs with their big wings.
Part of me wonders if the XL pilot was simply trying to fight it like a normal F-16 since it seems like it would have been too early in development for design-specific tactics to be developed. I suppose luckily for the prototype F-15E pilots, they still generally fly like other F-15s...
