*spoilers for Portal follow*

It would be lovely to know more about Chell, but what really makes Portal is GlaDOS. Personally I’d really like to find out more about when GlaDOS first flooded the enrichment centre with toxic case. The time when the red phone’s cord was cut (the commentary says the phone was to be used if GlaDOS became too aware, in which case she’d be shut off or something).

Something that would be cool, is finding out more about Aperture Science’s relationship to Black Mesa. I’d like to play out some sort of conflict between them, a lovely twist would be having GlaDOS helping you throughout, yet somehow you realise at the end that you’ve provided her with the trigger for her awareness and subsequent madness.

If aperturescience.com is to be taken as canon Aperture Science started off making shower curtains for the military (not sure which military), then the man in charge left 3 directives for the future of the company. The first 2 were absurd nutty things, the 3rd was to make a bio artificial intelligence lifeform operating system or something, which was really an aside as he hadn’t put much thought into it. Obviously the 3rd ended up being GlaDOS.

No matter what Valve does, Portal will be a hard act to follow.
They absolutely much keep the same voice actress for GlaDOS, she’s wonderful.
Just another 3-4 hours puzzle game would be fabulous too though.