I think there are a million ways to help a step child feel welcome, having their own bedroom, being fair, sensitivity, holidays. Your marriage is just that, your marriage. If you have your parents there though I would have your step children. No need for the honeymoon though.
It’s a minefield, being a SM. And it’s really important to take care of you as a couple, most second marriages fail, the ones with kids, so you’ll need special times together and absolutely do put yourselves first, some but not all of the time.
I was bridesmaid at my dads second wedding, but found it excruciating. Hated the dress. I’d have not in a million years wanted to join them on honeymoon, awkward! So it’s not always the right thing either, making the step kids central. Again, minefield. As the strong views here show.
It’s a marathon not a sprint! So take care of yourself.