Need to enhance the archviz roject

Hello Everyone,
Hope you all are doing good.please have a look.
I have been trying to get a realistic look by using natural lighting method(skylight and directional light). I have used bounce card method earlier and that came out pretty good but this method I am using for first time.
Kindly guide me further to make the scene more better.

Please have a look on attached images which I have been done so far.

Here is the update of previous scene. But it still needs many improvements. kindly have a look.

Let me know the suggestions to make to better.

you need to increase the lightmap resolution on many of your objects, you can see they are very pixelated.

Here is the Lightmap density of the scene.

(Ceiling resolution is 1084)

You can see on the ceiling and especially the floor that the resolution is too low. If it’s already a high resolution then you should try and split up the mesh into separate pieces and then redoing the lightmap UV’s on those sections–that way you can use multiple lightmaps.

Yes, The resolution of ceiling is 2048. But the floor is made in ue4 only then why it has low resolution.