In order to promote a more themely interaction between topside and the mix, I would suggest that GMs from time to time create a Macguffin placed somewhere topside. This macguffin should take coordination and teamwork to locate and acquire, and then be able to be delivered somewhere for a reward (or perhaps be an item that is in of itself a reward).
An example would be a shadowy NPC contacting a PC fixer and telling them "I need this rare unreleased episode of EGO that is in the NLM archives. I'll pay you 100,000c for it", while the MacGuffin itself is placed in game somewhere in the NLM tower.
At this point, the fixer has to hire a team to try and recover the item, while operating within the 100,000c budget allocated for the plot.
This similar plot structure could be basically applied to any corp, and gives an RP thread to mixers that is different than the standard 'Go blow up X corp because damn the man!'.
