I think it's quite common now not to have a first dance, or at least not a full dance. Sounds like you'll have a lovely day if you do it just how you guys want it! And it's a lovely idea to include your kids instead!
We're not married yet, but we aren't having confetti, a guest book, real flowers, a slow first dance song and we are having a sweetheart table for the wedding breakfast rather than a top table so we can enjoy our first meal as married couple just us! We've not had any negative feedback about the ideas! Hopefully you won't either