So just to re-iterate
Option 1. Get 16" Alloys with new tires and keep existing 15" with steel for winter.

Option 2. Get 15" Alloys and put the factory tires on them for summer, and get new winter tires for the steel for winter.

BTW I live in Calgary, AB, Canada where it snows quite a bit and was wondering if anyone has experience driving with the honda factory tires in snowy weather. I just want to know if they grip good.