Umaro has provided some missions legal and very optimized characters examples. As Critias has said, check his sig. If anything, they are a shade over-optimized for example characters, but then again they were not created as general example characters, but rather created so that a new player could sit down and be effective at a table with experienced players running characters with significant karma.
This second part I must say carefully to avoid getting another smite.
While I really like the Shadowrun game universe, and for the most part the current 4th edition game line, CGL is frankly weak with post publication product support. Errata, rules clarifications, official faqs, etc, don't seem to happen and probably are not going to happen. There is a very long list of things that end up being "GM's call" with this system because of slightly loose writing or unclear mechanics. I do think the core mechanics for the system are very sound, but there are alot of specific applications, stacking questions, interpretations of particular wording in the rules, etc, that have never been "officially" addressed. So a re-write of the sample characters from the core book isn't in the cards.
And honestly, I think I can understand that. GGL is a small company that uses alot of freelancers. Shadowrun is a niche game. I imagine 99% of the energy of the core development team is probably spent trying to generate enough sales to keep the company in the black and the doors open. Game design is a hard road financially under the best of circumstances and even more so for a product like Shadowrun. If they are going to pay someone it probably needs to be to make something they could sell, not to be head of the rules court or to make free downloads.