I think your plan sounds lovely!
We did the exact same thing when we got married. Except we decided to get married in the living room. I didn't want to travel to another location. We had little things appetizers that I had bought from Costco to eat. It was very small and beautiful.
I wore a clearance dress from Macy's that was just plain black so I can wear it again. Not that I get dressed up too often.
We had an official come to our house and do a SHORT ceremony. I think it took 15 min, but it still felt like forever....
For the cake we ordered it from the local bakery. I think it cost us $80 and it was two tiers. I was amazed that it was so cheap.
Later we went to dinner at a local restaurant (organic, local food) as I didn't want to cook meals for everyone but I wanted to feed them.
: The only problem with the food is the kitchen wasn't set up to feed so many people at the same time and my SIL thought she was being picked on as her meal was last.
But we expected something from her so it was no big deal.
I think the whole wedding cost us $600-$700 and the majority of it was the dinner at the restaurant.
We loved our wedding and wouldn't change it for the world.
ETA: My sister owns a nice camera so we had a family friend take pictures for us! Turned out VERY good and she wouldn't accept any $$ payment (we ended up mailing her cash anyway as I felt guilty) and she brought us a gift!