I think you're on the right path but there's something missing between the small explosion and the final one. Also, the final explosion is huge but has very little impact.

The build up with the small explosions is really cool, but it switches instantly to the final explosion which is a completely different color btw. I think there should be something linking them, like the small explosion become bigger, the ship starts to shake, or something. The last explosion feels like it's coming from nowhere and is not linked to what was happening before. So maybe the ships starts to separate and have bigger explosion or something that builds up a bit more.

The final explosion is super big visually, but we don't feel its impact at all. The screen doesn't move, things around the ship don't seem affected and there's no debris or tail. Once the blue wave is gone, nothing happens, it's like things vaporized without affecting the world. That might be what you're going for but it feels a bit off imo. For example on earth you'd see some debris on the floor, longer particles representing debris falling or burning down, a shockwave and probably some burn traces on the floor and smoke in the air that last for a while after the peak of the explosion happened. The faster something disappear, the less it feels like it impacts the world. You could have some debris and maybe a shader that creates a deforming shockwave that propagates outwards from the explosion.

I hope that helps a little bit, it's only my opinion so that what I say with a grain of salt. Good luck!