Good writing! VeraCrypt is a fork of TrueCrypt, which ceased to exist a few years ago. The reasons were never made clear but word goes they were forced by LEA. TrueCrypt in it's days was seen as uncrackable by LEA. Just before they stopped, the code of TrueCrypt was audited to see if there were any flaws. Apart for some minor things, it was rocksolid and to this day, nobody has cracked it. VeraCrypt went on where TrueCrypt stopped, and addressed the minor flaws found in the audit. Some other improvements were also made.
Password cracking can be done on 2 levels, a so called Dictionary Attack and Brute Forcing. A Dictionary Attack works with a word list. All the words are tried, even in combinations. Something is being used as an input, and if your password matches one of those, they know. "Friday13th!" would not be wise to choose. The thing is, it needs to be an exact match. If it isn't, it's not accepted as correct password. I do not agree that a sentence like "Iwouldlikeahamburgerforlunchtomorrow!" is a bad password. It will take a long time to find. Adding the so called keyfile, which could just be a picture or bunch of pictures of your favorite pet, makes it almost impossible.
For those interested, for several systems the hashes are precompiled and stored in a large database. Each possible password is calculated, and the hash is stored. Find a database with hashes and you can simple find the corresponding password. Rainbow Tables are such a technique. VeraCrypt is not one of them.
Going to Brute Forcing. Take a look at your car. Each km or mile you drive, one is added. Now imagine you get the car brand new, nothing on the clock. Furthermore, it does not count just to 9, it also counts from a-z, A-Z and every other symbol on your keyboard. Each combination is tried until the password is found.
To conclude : combining all computing power of all 3 letter agencies combined, none of them have ever ever ever succeeded in cracking a TrueCrypt volume. Giving a good password it is impossible, or too expensive or too time consuming. You would be dead before they knew. There is a tool for cracking TrueCrypt. It is called HashCat. It uses a bunch of video cards to produce a whopping 230.000 hashes per second (2013). That looks amazing and surely TrueCrypt would fall. But the total amount of possible hashes is 1.46*10^48. And I'm guessing there are more interesting storage volumes than ours.
One other thing no one mentioned. Our Operating Systems. Yes I'm looking at you Windows 10! You can store your video files in a TrueCrypt container and watch them when no one is home. But your OS keeps track of everything you do and watch. Windows 10 even sends data to Microsoft. They claim it is to improve Windows, but it is actually spying on you. Linus explains it in a nice video :
So, in order to keep yourself out of trouble, using VeraCrypt is a good start. Best is to use it also on your Operating System. Shut it down and nobody knows what you have been up to. There are way more advanced things you can do but I'll leave it at this.