I know, I know, I just keep procrastinating on that darned Oblivion Gate!

I prefer to wait until my character hits level 10 before I close the Kvatch gate and retake the city. I think my current character is about Level 7 right now, so it won't be too much longer.
As for my plugins...
You need TES4LODGen to use them.
Are you loading those plugins into the game? If you are, SOMEONE didn't follow the instructions properly, and SOMEONE should probably look over the readmes again.
What you do is put them into your load order, activate them, run TES4LODGen, and remove them from your LO again when you are done. I primarily designed that mod for people who already use LODGen (RAEVWD users, for instance) because generating LOD while KR is active caused the walls to double, resulting in a very annoying flickering effect.
I take it you've already passed the point where the chapel was being rebuilt? If so, you will want to use the "Restored" plugin, as that will allow you to see the walls no longer burnt and (if using RAEVWD City Architecture) you will be able to see a few buildings inside the city, as well (chapel and arena I am certain of).
The mod addressing the night brightness is likely All Natural (if that is what you are using).