Welcome Roberta (and really nice shots there! I really like the reflections on the water and the city lights).
I can sympathise with always being too close to the fireworks because of the landscape of the area. I have the same kind of problems and I usually just wind up tossing the pictures from the grand finale because they so often are overblown. The one thing that I have done is to use a quicker shutter speed and a smaller aperture, but that has the effect of getting rid of any sort of background completely. So then what I have tried is combining multiple shots to create the setting. This would be the beginning of the finale so the fireworks weren't really over the top yet.
Still, more often than not, the finale just winds up with too many lights for me to effectively capture. I think you have the right idea being further away from the fireworks if you want to capture the finale.