Lightmapping problem, textures appear blocky

Hi all, I've tried searching for a solution to my problem but haven't been able to find any answer, probably because I'm not really sure how to describe it.

I built this scene and put lights everywhere, it all looked lovely and wonderful. I set the level to static in the inspector pane. When I try to bake the scene, it renders the lighting very irregularly as if it pastes a single constant lightmap onto some objects. The result is the level looks like a checkerboard of lightmaps in parts. See here:

https://pbs.twimg.com/media/BWZf_9dCUAAIaVY.jpg

When I change the bake to single lightmap the blockiness goes away but the level looks flat and lifeless. If I uncompress the lightmaps, the file size balloons to over a gig and the problem still remains.

I built this scene in Unity Pro trial version and am now using the free version, since my trial expired. In my project settings>player>render settings I've it set to forward lighting but changing it to deferred doesn't help.

I'm not very experienced with Unity and my laptop isn't terribly good (baking the scene takes forever), so please go easy on me here.

Can anyone help me out?