if you're not happy with your placement i'll let everyone except finn move their guy 2 squares from their current placement to where they deem appropriate in regards to where they'd be. finn was pretty specific as to where he was.
little blob guys arent really tiny, but are displayed as such so they can glom onto you and still be visable on the map. they're actually classified as small creatures.
grey is difficult terrain from the roots tearing it up. shelves are full of non-flammable but heavy objects and can be tipped over, alchemy tables have all manner of flammable items on them if tipped over