I'm really traditional about weddings. If it were me, I would want to have the children there (his and yours) and whatever family and friends who can come.
I made a wedding for my sister in my house, her second wedding. It only cost a few hundred dollars for sheet cake and sandwich platters. I even put cheap bunches of flowers in vases from my house and made cute center pieces on folding tables. My family are musicians so it was a big jam session. The bride played drums!
It is a coming together of two people and two families.
But-- you can definitely elope and do whatever you want.
Honestly, ordering cake and platters took minutes. I moved the living room furniture away and put up card tables. It was really nice.
And talk about embarrassing relatives! If I thought my family was strange, the groom's family was much worse! We laughed.
Congratulations and enjoy whatever you do. Oh yes, and you have to invite all of us on PC