Careers allows you to create a public profile page where you can publish your resume, best SO answers, etc., allowing you to link from careers to your SO answers and your SO profile, but there's no good, easy way to link the other direction.
For people actively looking for a job or open to options, letting the user link from their SO profiles to their Careers page would be a great way to drive traffic to their Careers profile. At least for me, my SO profile page currently ranks a lot better than my careers profile page on Google and linking this direction would bring a lot of traffic to careers.
I envision a "Display my Resume" checkbox in SO that adds a big orange "See my resume" button in the SO profile page. (ok, maybe not that big... or orange)
A second suggestion would be to at least let the user link it's careers profile to stackexchange "network profile".
I'm sorry if this already been proposed (I searched, really! But the only similar question I could find accepted an answer which is not what I'm really looking for).
Ps: The mentioned similar question was answered with something like "Just put a link to your career profile in About me". Although this is a fair answer, what I'm asking here is if anyone else thinks that a deeper kind of integration would be useful.