The most important issue prompting Americans to rebel in 1776 is clearly Parliamentary taxation. This began early in colonial life with the system of mercantilism. The long and short of this system was an effort by the British to ensure a favorable balance of trade between Britain and the American colonies. There were numerous laws requiring all goods purchased by Americans to come directly from Britain regardless of where they were originally produced, while in Britain they were subjected to taxation which raised the price to the colonists. Simultaneously certain colonial goods were required to be sold directly to Britain at unfairly low prices for resale to the world from Great Britain. It also required that all goods to and from America were to be transported on British ships. So the colonists basically became pirates and smuggled goods from America to other places and then different goods back to America. Smuggling became an important source of wealth for many Americans such as John Hancock. The mercantile system was only an annoyance to the colonies until approximately 1763 when for the first time the British set out in earnest to enforce the mercantile system. The result was alienation of the colonists who had up until that time sought only to claim the "rights of Englishmen," not to separate from the mother country.
This annoyance was exacerbated in 1763 by the strict enforcement of the navigation laws, and the sugar act of 1764 which was the first law passed by Britain for raising tax revenues in the colonies for the benefit of the crown. This caused bitter protest from the colonies and the duties had to be lowered until the agitation had somewhat died down. The resentment began again with the quartering act and the stamp act of 1765. The stamp tax was the most odious measure of all. The stamp act mandated the use of stamped paper certifying payment of tax. Stamps were required on bills of sale for numerous commercial and legal documents, among these were playing cards, news papers, diplomas, and marriage licenses. The British army enforced this measure violently which prompted the American cry of "no taxation without representation." The Parliament was ultimately forced to repeal the stamp act due to colonial protests and riots. The Townshend acts of 1767 imposed new taxes on glass, lead, paper, paint, and tea. The colonists, happy with victory over the stamp tax, were in a rebellious mood and protested violently, precipitating harsh enforcement by the British army. A colonial mob attacked a squad of ten redcoats which prompted the army to shoot into the crowd, now known as the Boston massacre. Through it all the Townshend acts nearly provoked rebellion but failed to generate significant revenue.
The restriction of civil liberties was also a very important component of the revolutionary fervor and was happening at the same time. The stamp act, in addition of being a tax, was a measure designed to restrict rights of the colonists as Englishmen. It provided for trying of offenders in the admiralty courts without juries, the burden of proof was on the defendant who was assumed guilty until proven innocent. The act prompted a demand on the part of the colonists for representation in the British parliament, which Parliament ignored.
The principle of "no taxation without representation" was very important and the colonists clung to it tenaciously. When the British stated that sovereign power of government could not be divided between authority in London and authority in the colonies, it forced the colonists to deny the overseas authority completely.
Parliament also began to assert its supremacy over the colonial assemblies. The same year it passed the quartering act which forced the colonists to house and feed British troops without the consent of the colonists. Following the rejection of the Townshend tea tax and the Boston tea party, Parliament passed the intolerable acts of 1774, which came to be known as "the massacre of American liberty". This act closed Boston Harbor until damages were paid, it restricted town meetings, it allowed British officials who were charged with the murder of colonists to be tried in England. It also included the Quebec act which took land earmarked for Protestantism and gave to French Catholics the Northwest territory stretching south to the Ohio river. Another important factor that lead to revolution, which was thoroughly inseparable from the taxation issues and the abuse of civil liberties, was the harsh and heavy handed enforcement of the odious acts by the British military. Each and every time the colonists were out of order the only method available to the British of restoring order was to send in the military, which to the colonists were "red coated ruffians" whom they taunted as bloody backs. Following the Boston massacre, only two of the soldiers were found guilty of manslaughter were then branded on the hand and released. The colonists were outraged.
Yet another factor leading to the revolution, though quite possibly of lesser importance, was the legacy of colonial religious and political ideas. By the time of the revolution the colonies were religiously fragmented. The Anglican church, the official church of some colonies served as a prop for kingly authority. This angered Congregationalists, Presbyterians, Quakers, Baptists, Catholics, and virtually everyone else. The Anglican church did not serve the needs of the people, it didn't hold up its promises to the people, holding true to English authority. The Anglican church had a notorious reputation for clergymen with loose morals and worldly lifestyles. The British tried to impose the Anglican church on additional colonies to everyone's displeasure. When the Quebec act came along granting large territories to the defeated French Catholics, the colonists feared that protestant religion would suffer. It was more than the colonists could stand, particularly when coupled with the issues previously discussed.
It certainly is a fine thing to compare the relative importance of the four issues and the relative importance of each in regard to the revolution, but in reality every person that revolted probably revolted for their own individual reason. Some may have revolted for repression of religion, others for taxation, others for deprivation of civil liberties, others for oppressive military actions, and still others for reasons not discussed. Collectively however, they did revolt. A more overriding reason for revolution, something that had to have been common to all revolutionaries, is the fact that the opportunity to revolt presented itself with some likelihood of success. Otherwise this revolution would have been led by maniacs and fools, rather than solid purpose driven citizens like Benjamin Franklin, and certainly would have failed.