For outbound links, what is the best SEO structure?
Remember OUTBOUND links are of little value to SEO, so don't stress it too much. It's the INBOUND links that matter to you - that is, links FROM other companies TO your website. For those, you IDEALLY want keywords INSIDE the link, or if not INSIDE the link, nearby in text. I.e., <a href="http://www.sealightstudios.com">Amazing Kauai Wedding Photographer</a>
Now, for your OUTBOUND links. First, keep them in your keyword communities - Wedding, Photography, and Kauai (possibly Hawaii). Don't link outbound just to anything. If you aren't getting something in return, then use the NOFOLLOW attribute. Links are sort of like MONEY don't outbound link if you aren't getting something in return.
Reciprocal links in your keyword community probably DO help SEO. Just keep them in your target keyword communities, and remember what you really want is many, inbound links, in your keyword community, from high PageRank sites!