Just like Layout 2015, Layout 2017 (Mac) exports un-optimized PDFs, so I have to (usually) do the extra step of optimizing in Acrobat. Kind of nice to not have to do that. Example: PDF comes out at 49.6MB, when it should be 8 or 9 MB. Also, another weird thing I found is it doesn’t matter what the JPEG compression is, the file size is always the same.
I have not really tried all the options. I always follow the same workflow as you do, especially as IMO the JPG compression artifacts the exporter produces are very ugly whatever the compression level so I always keep compression off. SketchUp/LayOut is not alone in this. The BIM applications I use (Archicad, Revit) also produce PDF files that Acrobat is able to compress very much without a loss of apparent quality.