I believe the issue here will be that a "skill" is in fact a "tag" and hereby can't be handled in the same way as the other profile fields.
It would be nice however that you could use the skills as well as a selection criteria for the streams. Maybe worth launching an Idea in Ideas for Jive
Not sure if it's feasible but you could create Jive user groups per skill and link those to a stream.
Probably possible to automate this via API I guess.