Magento 1.9.1 Porto theme
We had perfomance problems with the hosting company. They migrated us to their best VPS machine/node and now things seem to run rather fast except for when going through the order from one page to another - it takes way too long. In other words - the front page seems to load fast but clicking something like Add to Cart or Proceed just seems to take many seconds. I tried searching the Internet for possible reasons and I now suspect that it could actually be some external process that is being contacted that the site has to wait for. We have Paypal (Paypal Payments Pro and the Paypal Express Checkout), I also inserted the Google Analytics Code in different places, we still have a Shopgate extension installed which we are no longer using, a sticker on the top of the page which says: Our site is Shopper Approved (we have the Shopper Approved extension), and we also have 2 calendar extensions (one by Amasty and another by BSS Commerce).
Is there an easy way to figure out if any/which one of these things maybe causing our slowness issue? Anything else I could check? I already cleared the log files. If I turn Paypal off to test, will I have to reset it up all again? (it's a rather involved process it seems).