Hi,
A google plus local page could help for local rankings, especially when Google SERPS return a 'local 7-pack' of results.
In my experience I have not seen many Google SERPS with G+ Local listings showing in the results for web design / seo related queries. However, I have seen Google show a G+ Local listing for one SEO company in Milwaukee, Wisconsin because they branded themselves as the "Milwaukee SEO Company" with a matching domain name, but this seems to be the exception.
When you say 'Google Plus Local page', I assume that you mean a Google Plus Business Page created in the 'local' category.
At this time you can only merge a G+ Local listing with at G+ Business page that was created in the 'local' category, however service area businesses (SABs) do not qualify for this merging at this time. Meaning, that if you are required to hide your address in your G+ Local/Google Places dashboard (if you only service customers at their location and/or customers do not come to your office), you most likely won't be able to verify your G+ Business page, so they wouldn't get merged either.
