I'm expecting about 75-100 people at my baby shower :/ we have to rent out a place it's crazy .. Anywho I really don't wanna open ALL OF THOSE gifts but I can see how people may feel it's rude or ungrateful.
So I came up with two ideas:
Opening gifts as the people walk in
Opening gifts table by table...
I would designate a couple people to help you open gifts. With each of those people have another person to write down what the gift was and who it's from so you can send out thank you notes later on. If you have an older child you could have them help open gifts and your dh as well if he'll be there.