Course File Size - How big is too Big

I have a course that is 1.3GB due to multiple videos. I have not even added audio yet. This scares me.  It takes about 20-30 minutes to publish as it is. It is definitely not fun to publish multiple times at that size.  I am working on saving my video files at a lower quality so the publishing won't take so long.  Then I will have to re-import them. Hopefully that will help.  I tried publishing with the low video quality option from the publish page, but it still took just as long to publish. I just pray and hope my file does not get too big that it won't open anymore.  Can this happen?  I am working in Storyline 2.