Try allocating more RAM to the game. You can do this by:
- Opening the Minecraft Launcher
- Clicking on 'Launch Options'
- Toggling 'Advanced Settings'
- Clicking on the profile you want to use
- Toggling 'JVM Arguments'
- Replacing -Xmx2G with -Xmx4G. This changes the maximum amount of RAM Minecraft can use to 4GB, which should be enough.
I am using a MBP 17 inch Early 2011 (Intel Core i7 2.2Ghz, Radeon 6750M) and I get >100FPS, So hardware isn't a problem.
Hope this helps!
Are you running shaders or anything? Minecraft is notorious for crippling even high-end builds with shaders.
Also, try turning your render distance down.
Referring other youtubers is fine, as long as you credit.
For fonts, I would use http://dafont.com. They have some paid fonts, but some are free! Note: If you plan to monetize your videos, it counts as commercial use. Have fun!
In that case, most games use more gpu power, so I would go with, like @Ansger said, a 1070/1080, depending on how much you're willing to spend. That G-sync monitor is also a good investment.
Good luck!
If you can spend the money, getting a new CPU might help, although stuttering seems to be a software/network issue. Also, If you haven't, try overclocking.