Echoing what others are saying about the Tomorrowland bridge. I'll add however that if you don't mind having your view of the castle obscured, stand in the spot where the tree blocks your view. The fireworks will appear to the right of the tree so your view of them will be unobstructed; Tink will fly just to the left of directly overhead, making her a little easier to see without hurting your neck; and this is usually the last portion of the bridge to fill up, either because people want to be able to see the castle, or because they don't realize that they'll be able to see the fireworks from here (my guess is the latter, since it usually fills up very quickly once the pyro starts). I'm usually able to get a spot at the railing within five minutes before show time. On a busy day the hardest part is usually pushing your way through the people packed shoulder to shoulder trying to avoid this area.
I've never watched Wishes from Tomorrowland Terrace before so I can't say for sure, but its always seemed to me from the geometry that the overhang might cause you to lose sight of Tink from there while she's still pretty far out. Maybe someone who's done the dessert party can weigh in...