Full of ideas and questions I am... here's another if you'll entertain it.
Some of the beam weapons are pretty weird looking:
They're often solid colors. Probably more realistic but also kind of boring looking.

They go 'through' targets that aren't destroyed yet.
They 'end' too abruptly. I'd imagine a beam of light fading as it dispersed, instead of being perfectly continuous with no fading, then ending like a piece of string that just got cut by scissors.
I don't have any idea how much work it would be but I think they would look better if:
They had more effects to them.
They stopped on impact with another ship (unless that particular shot destroyed the ship).
Missed shots faded out over distance, rather then ending abruptly.
For some of the effects that could be added, something like Homeworld's beam weapons would be pretty cool. Again, I have no idea how hard it would be to do, I'm just throwing it out there to see if it's something you'd be interested in.
Here's a
link to some Homeworld 2 lasers on youtube, they explain better with actual visual imagery than I can probably explain with words. At the time of this clip, you can see a laser that has 'tendrils' of power running along its course. You may have to pause it right away (about 1:01 to 1:03 is good) after opening the link to get a good look. That kind of thing. Something with more effect that conveys the enormous power being transmitted over several kilometers at the enemy.
Of course... I'm sure 'real' spaceship lasers wouldn't look like that, but honestly, I think 'real' spaceship lasers would be nearly invisible anyway.