I am doing something similar, in hopes of building brand awareness. Though I am imcorporating sub domains more so.
Example....
www.southplatte.com - main site
www.southplattetech.com - computer sales/service (same as biz name but it points to tech.southplatte.com)
www.southplattetreasures.com - same as biz name points to treasures.southplatte.com
My hope is to optimize the TLD's for search engine placement and doorway pages, then link/redirect to the sub-domains.
I am not sure how the
SEO works for sub-domains, or for the doorway pages anymore (they used to be good for search engine placement).