I do wonder what Airfix base their choices on.
It did look like the new Spitfire IXc was well received. A new Me109 or P-51 to the same standard would possibly have similar reaction. Or re-release the Mosquito with the BIV as an option?
The 1/48th Sea King,, Buccaneer and Gannet looked good as well so another 1/48 foldy like the F-4K could have all the options of their 1/72 version but without all the many extra parts. Or just re-release the Sea Vixen.
If they did the Angel Interceptor in 1/72 or even 1/48th I would enjoy a simple all white scheme. Or just re-release the TSR-2.
Some Thunderbirds or other TV classics like DSV Liberator, Stingray or Fireball XL5. Or just re-release Wallace and Gromit in time for their new film.