The 10 commandments are special because an event happened in which God specifically "gave" directives. Putting this into context, He had just shown His power to the Hebrews by mocking the alleged power of ten of Egypt's highest ranking gods: thus, literally declaring His dominance as the Most High in liberating and leading the Hebrews to a better place. Now, there were many other commandments given by God that were, are and will always be "in effect/important," but the 10 commandments were specific directives outlining a new agreement: the Hebrews will be His people, and He will be their God IF they follow the ten directives. The Hebrews could always do what they wanted and test their luck on their own; they had that option, and many did that.
The 10 directives encompass the entirety of law. Commandment 1 is a covenant of allegiance to God, if the Hebrews chose Him. Commandment 2 reminds the Hebrews not to make any perceived art, images, sculptures, etc. of the spiritual world especially out of worship. This is also because Egypt was full of occult practices that openly used graven images to "draw power" for rituals and the gods. Commandment 3 underlines His holiness, and further accentuates His power, and His dislike of vanity especially when relating to Him. Commandment 4 was a reminder to the Hebrews to abandon slave mentality. No need to work every day like in Egypt when He - their God - even took one day off. So, the seventh day is a day of rest for a communion with God. But, you can not do servile work more than one day.
Those are spiritual laws (4).
The last 6 are all about how humans should interact with each other: honor/respect parents, no murder , no stealing, no committing adultery, no lying/bearing false witness, and no envying what your fellow man has.
10 is a spiritual number for completeness.
4 is for material creation and completeness.
6 is the number of man.
The first four commandments contains all necessary for creation to exist with God. The last six contains all necessary for created man to live with man. The first four make up a spiritual covenant with God, and the last six make up what is supposed to be a human covenant with man. Together, you get a complete (10) overview and guide on how to be a man of God. An entire Bible's worth of rules in ten mandates - if humans were that obedient, wise and righteous. As before the commandments, since the Hebrews constantly rebelled and didn't learn, He had to give specifics. You would think you wouldn't have to write a rule about witchcraft when He already gave commandment 1. Or, perhaps there would be no need for a rule about rape and violence if people were wise enough to compare it to commandments against stealing, false witness and coveting.
Skip three thousand years or so into the future, and Christ condenses it into two commandments. Now, two is a spiritual number for division, or duality - like knowledge of good and evil , so it should have been even easier for us to understand these commandments on a carnal level, yet there is confusion. Parenthetically, these "two" commandments on which the whole law falls foreshadows the two dual fighting natures of humans being perfected in unity through Him: perfect spirituality (1,) and perfect morality (2) contained in the perfect man of God (Christ, others who follow Him.)
Love God with all of your heart, might, and soul = obeying the first four commandments
Love your neighbor as you love yourself = obeying the last six commandments.
Now, first four commandments are spiritual covenant mandates with God: so any rules accordingly come up under this category (like idolatry, witchcraft, etc.) The last six commandments are man-to-man covenants, so any laws accordingly come up under this category (stranger relations, relationships with relatives, property, honor, business, etc.) So
Love God with all of your heart, might, and soul = obeying the first four commandments = laws pertaining to relationship with God
Love your neighbor as you love yourself = obeying the last six commandments = Laws pertaining to relationships with man.
On the two "great laws" of Christ, therefore, fall the entire law, and how to be a man of God fully. So, nothing is lacking in the ten commandments, the Law of God, or in Christ.