In this thread there are more information about who the different characters are based on, if you want it:
http://www.enworld.org/forum/showthread.php?645264-X-Men-in-Zeitgeist
Below are some of the pieces of information (probably not all):
- Gale and Tinker Oddcog were both originally sample superheroes from our 2002 book Four-Color to Fantasy
- Alexander Grappa (inspired by the idea of Professor Xavier, but only telepathic with constructs) trying to escape Leone (directly inspired by Magneto)
- Thames Grimsley is Shatner.
- Delft is Mark Sheppard
- Aodhan is Clarke Peters
- Roland Stanfield is JFK.
- Captain Rutger Smith is Che Guevara.
- Patrick Stewart is Verzubak Tantalovich.
- Pemberton might be Daniel Day Lewis in There Will Be Blood
- Nevard Sechim is Bill Cobbs
- Gale is Katrina Kaif
- Asrabey Varal is Shahrukh Khan
- Mr Mapple is EN world user Teflon Billy
We might as well collect them all in one place. Also I am pretty sure that Rock Rackus is Kanye West.