Im working on creating my 1st theme template for a number

Im working on creating my 1st theme template for a number of niche sites. Right now my site is so slow its unbearable. (ie takes a full minute or longer to load) Im not sure if its because of the number of plugins Im using or an issue with my web host. As of now Im using shared hosting, using Dreamhost, but am planning on a dedicated server once I get more clients.

I have 2 main issues:

1. Very slow website:

Template site: http://www.chaptersites.com/theme1
Wordpress template: Stark theme from Theme Forest
In wpmudev dashboard I installed most of the plugins available.
I can provide a screenshot off all the plugins enabled and/or ftp and/or un/pw for site. Please let me know?
In my Network Admin plugins there's 78 plugins, with 41 active. The vast majority are mpmudev plugins.
Please go to http://www.webpagetest.org and put in http://www.chaptersites.com/theme1 to see what I mean about page speed. Please advise?? Im not sure how to consolidate all this. I see there's a lot of files loading here.

I am using:
WP Super Cache
WP Widget Cache
WP Minify
DB Cache Reloaded

None of these seem to do anything. It looks like some .js files are being loaded twice (ie prettyphoto.js for starters) but I'm not sure how to fix this.
I was hoping that wpmudev plugins all worked together in that if one plugin called a file and another plugin needed that same file, this needed file would NOT be loaded twice. This does not appear to be the case. Please advise??

2. Random redirects to website homepage:

Perhaps because the site is so slow or server issues, it randomly goes back to the website homepage.
For example: I may click "Edit Page" in wordpress admin bar, on interior page, and it goes to homepage. I may click on "Events" in admin dashboard and it goes to homepage. I may click on "Settings" > "Reading" and it goes to homepage. Or any link for that matter (in admin dashboard or not)...
It appears to me as if the server is timing out and just defaulting back to the website home page. But sometimes everything works, other times it doesn't.
I'm not sure if this is a server issue, due to shared hosting, or due to the shear number of plugins used, or something entirely different?? Please advise?

Thanks for the help.