IMHO If you're mainly a console guy - go the DFC, you will be fastest in an environment you are best used to.
If you're mainly a PT guy, used to mixing in the box, go the ICON.
If you're a console guy interested in flirting with some PT integration, go the system 5.
For TV, I dont think much can currently beat an ICON. Custom groups, templates, PT ...
I had the privilege of using an Icon back in film school. I wasn't doing any speed mixing back then, but i remember the features of the desk being very intuitive.
Having dedicated buttons for auto preview and write to selection (and within easy reaching distance!) was fantastic for writing automation.
Custom fader groups are great if you're working from a ...
FWIW I use KeyRemap4MacBook to get some of the functionality of the numeric keyboard. I use the option "Change Num Key (1…0)" and then it becomes a matter of fn+1 fn+2 and so on to access that functionality.
I'd say take the job anyways and give the best you can. Sound Designers are storytellers too and I think if the director is not involved so much in the process, you can create something which you think will tell a story better, sonically.