I have my surname and my partner and DC all share his name. I'm very happy that I have my own name (I also publish using it, but would keep it anyway even if married) - I like that it says I'm independent. I think women changing their names to their husbands' is insidiously sexist and not as harmless as people make out.
But about the kids - in an ideal world they would be double-barrelled or just have two surnames, one after the other, and they could choose which one, or which order, they preferred when older. Actually, we did not use my name for other reasons - it is very unusual and I didn't want them to be able to be searched for using my name (long story). But DP wants them to have his name and I can see why. Everyone knows I am the mum, I go through pregnancy, I give birth, I'm on all the records. Giving them his name is a mark of his connection.
Yes of course he could have a connection with them anyway, and you can have your dad's name even if he's not the biological father, etc etc. But for my DP, it makes him feel included and known as their dad, it's important to him - and I don't mind. They seem fine with it too. They know I have a different name.
Whenever I have to explain it to people I just feel happy that I'm not Mrs Husbandsname. Could you see it as a positive too?
However I think you could just give him your name as another surmane: Baby Middlename Yoursurname DPssurname
He may generally be known as Baby DPssurname but at least his full name would include yours.