Twig help or hindrance

A demonstration of what I'm doing is show in video below.

It is essentially an expression engine clone... where you can add arbitrary fields and customise any website page. As you can see in the demo it dumps twig syntaxed code into the view files. But like I was saying, the end user might want to do a bit of jazz with CI inbuilt functions or even vanilla PHP? What do you think?

http://recordit.co/ErScplTq0r

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