Premiere Pro Import OR Opening Project - file hangs at 69% or 70%

You've got way too big a project there for 'stand-alone' old-style projects workflow. As ... all those assets are loaded into RAM/cache files on open, and it's overloading the system clearly.

I would suggest going to Productions ... it's a way different model, you organize by subfolders of your Production folder, and use project files within the subfolders like you use bins to hold things.

Like a subfolder of the Production for media, with maybe even subfolders for type or day or episode. And within those, project files that hold the specific media or other assets.

And another subfolder for say sequences ... with projects for holding the sequences within them.

There is NO duplication of assets across projects within the Production, it doesn't overload your system, and is how the BIG organizations run features and docs and even entire years of episodic work.

I've gone to it for my one-man shop, as I can have all my sound library, b-roll, temp sequences, all of it ... available to any project for any client I work with.

And their documentation for it is by far the best they have made for anything in Premiere, probably because it seems that Jarle Leirpoll was the lead author.

Plus there's a ton of things for anyone doing any work in Premiere to know.

Neil

Premiere Pro Productions Introduction

Using Productions in Premiere Pro

Adobe Long-form and Episodic Best Practices Guide 

Jarle’s blog expansion of the pdf Multicam section: Premiere Pro Multicam