I don't think his opening is necessarily all that different from what the others got. Gale literally appears out of nowhere and Astarion just is standing there and then ambushes us. I agree that having Wyll join the gate battle without a cut scene nut also no interaction is a strange choice. But I also like that our first real encounter with him is one where, I feel, he's at his most sincerely good and genuine. I'm curious to see what his introduction is like now.