Question: **EDIT:**

Calculations were incorrect, the earth in my comic is not 5.8x larger, it is 2.4x larger. Its surface area is 5.8x larger but the diameter is 2.4x larger.

Anyway

I'm working on a comic that is set in an alternate earth that is 2.4x larger than the real world in an effort to incorporate numerous fictional locations that could not fit on a real-world map due to their sizes.

I am wondering if earth that is 2.4x larger would slow down human progress to a significant degree due to the fact that travel times would be extended, thus slowing trade, immigration, and colonialism. 

This comic aims to be set in a modern world albeit on a larger Earth. The USA still exists but it's a much larger country. New Jersey, for example, is now the size of England. Likewise, the repercussions of this larger earth may inhibit the USA from ever coming into existence. 

If the answers result in any conflict with the goals of the comic, I may just resort to pure fantasy but it will be fun to learn how this stuff works regardless.

Answer: 
It depends. Remember that most (all?) historical civilizations developed within fairly limited areas: the Nile Valley, the area around Greece & later Rome, the eastern coast of China, &c. So they could perhaps happily develop their own civilizations on a larger planet, ignoring the rest of the world - as for all practical purposes most historical ones actually did.

Now what could cause a problem is that if you are just scaling up Earth, with all the geology & geography otherwise the same. The problem is that to have a Bronze Age, you need copper and tin in reasonable proximity; likewise, to have an iron age you need iron ore and coal. Are your world's Phoenicians going to be able to sail 5.8 times as far to bring back tin?
Even if the density of that planet is smaller than that of Earth, so that the surface gravity is the same, the gravitational well is deeper. This means space travel is much more difficult. Crewed spaceflight possibly would not be achieved at this technological level and the number of automatic satellites is much smaller. Putting just a tiny can in the orbit is a huge endeavor.