You could use SW to do the 2D stuff, but that's an expensive alternative. Better to use Draftsight, which is free from Dassault, comparable to and compatible with AutoCAD.
I believe you can insert the pdf's into a drawing without a lot of trouble. Here's the work through (in my mind)
create an empty part file that will go into your assemblies (this allows the assembly bom's on your drawings to reference the item)
create a drawing and insert a view of the empty part file (this will associate the part file with the drawing as well as allowing all info in your custom properties to propogate to your drawing)
Insert the pdf onto your sheet:
Select 'create from file', browse to your pdf
Here's what you get:
Note that you can double-click on the 'object' and it will open the file