An explanation to why a character in Shadowrun should be specialised rather than a jack of all trades. The discussion in the comments get a bit heated over this though and point out that a team with duplicate roles can function just as well without pulling people out of the spot light.
Seems like a lot of work to handle for an inexperienced Shadowrun GM so best to stick to one person, one role at the beginning.
On the surface a jack-of-all-trades seems like a good idea. In a pinch, you can fill in for someone not there. Mage player got a case of the flu? Game on, I can sling spells! Face player out on a date? Well, I have social skills and two contacts, LET'S DO THIS!!