No, actually, I don't really like the Xeelee sequence. But my objections are with the characters and storytelling, which I just can't connect with.
I'm assuming that you're reacting to what you see as 'fantastic' or 'unrealistic' science, when, in fact, the ideas in the Xeelee books are grounded in a very strong understanding of the Standard Model and modern cosmology.
Either that or you're terrified that it didn't go the HUMANS FIRST **** YEAHHH route.
I have a bridge to Terabithia I'd like to sell to you...
Is there a particular part of the science you'd disliked? Kerr metrics are real, the baryonic/dark matter distinction is real, the Great Attractor is certainly real...
the executor class star destroyer
19 K's long
Take a look at 6:20
Seeing that a few fighter laser blasts and a torpedo were enough to knock out some of the Executor's shield arrays, I bet a beam cannon could make short work of said shield array, waste the bridge, and proceed to use the gap in their defenses to melt a hole right through that ship.
We have no idea what the yield of a beam cannon is compared to the yield of Star Wars weapons or the power of Star Wars shields.
The comparison is fundamentally ridiculous. (Especially as we see Star Wars ships using beam weapons against each other.)
Firstly, Freespace caps don't have shields at all, though we know that the Lucy had. They were meant to take a lot of damage, because they were already heavily-armored. Ever wondered why the Colossus has only 30,000 in it?
Either most of the crew were just drones, or most of the supercap was spent for armor. Also, Star Wars fighters could be so-advanced that they could carry lasers enough to break an Orion in about 30 rounds. But again, we're trying to balance the two.
The Shivans had technology much above mere beams. I presume, for certain, that they can manage to create some kind of mysterious charge that disintegrates matter - for instance, the Hallfight in Descent. That last one who died just disappeared after a Shivan created some unknown kind of energy. And, also, how could 90 Saths detonate a star? Probably that kind of energy, again. We saw that each of the Saths joined their four arms and had some kind of electric-charge linking them together. Then we see an enlargening white sphere, followed by the destruction of Capella. Recall the Hallfight. We see this Shivan, enlargening a strange white sphere, followed by the destruction OF the boarding party member. Similar.