As much as possible. As you go through the story, tasks that need more multijell will turn up and you might have to grind collection for a while.
The one problem is I really the game was longer, since once you've sorted out what your doing and where your going, its over relatively quickly.
Also, you often have to pretty much just sit around and wait for an upgrade to show up, or at least keep exploring tasks until you run across one.
I also wish they'd chosen a slightly better alexa voice for Gamma, since her personality is a bit ditsy, but her voice always sounds as though she's terminally depressed. This is odd since the other robots all sound okay.
At some point I'm tempted to restart and then grind multijell until we can assemble the new robot delta, since while we could do that now, there's nothing for delta to do at the moment other than repeating gathering multijell tasks since we've come to the end of the actual story.
With our dreaming and singing, Ceaseless and sorrowless we! The glory about us clinging Of the glorious futures we see,
Our souls with high music ringing; O men! It must ever be
That we dwell in our dreaming and singing, A little apart from ye. (Arthur O'Shaughnessy 1873.)