Hi,
You have that constantly updating Twitter feed. The data is coming from another source, and doesn’t show up just once, but goes on forever. So that’s an obvious bottleneck.
Not only that, the script that’s running it is also hosted elsewhere, on a different Twitter server. So if there’s any delay on those ends, your speed is automatically borked, with no way for you to control it.
Frankly, I would be very surprised if you didn’t have slow loading. If Twitter slows down, so do you. And it frequently does.