By all accounts, Prince Arthur was very different than his boisterous, self-indulgent, charismatic younger brother Henry. How would English history have been different if he had not died prematurely?
There would have been no issue about the consummation of his marriage, to be sure. There would have been no government-driven Reformation, and fewer frivolous French wars. It is fair to assume that he would not have had a son with Catherine. This would have been less of an issue, however, because Henry would have been married to a French princess; their union probably would have produced male heirs. The Tudor line would consequently have continued uninterrupted after Arthur’s death in the 1540s.
England would have remained a completely independent Catholic country, with a foreign policy based on the maintenance of the balance of power. Wolsey would have been a much smaller figure, and no one would have heard of Cromwell. An institutional battle with Parliament was still on the horizon.
In short, the specifics would have been quite different, but the overall direction of English history would have been fairly similar.