Keep in mind that most of the Lake View rooms do not have a fireworks view. They are oriented toward the Poly and the TTC. There are a few that may have a partial fireworks view. There are 3 or so Standard View rooms that have a great fireworks view, and there are some other SV rooms which have a partial fireworks view if you stand at the edge of the balcony and look hard right.
There are so few fireworks views, that I would not recommend even trying for them. If anything, ask for upper floor and lower floor. If you want a chance of fireworks, get standard view and ask for upper floor, pool/main lobby view.
I have stayed there probably 6 or 7 times. Only once have I got a great fireworks view. We did not request it, just requested an upper floor. Once we had the view where you can crane your neck to the right and see them.
Note: the SV 1BRs with a great fireworks view are 1327 and 1427. There is no 1BR on the 5th or 6th floor with the great view. 1127 and 1227 may have a partial view, but may have obstructions from other GF buildings.