One point you have to firstly absolutely concede was that the Spaniards blackmailed their colonised into Christianity in a way that the Brits opted out of doing.
The reason for this, to be fair to the Spanish, is that the agenda of the British was very rarely 'dedicated' to any one land they colonised. They knew if that particular land happened to oust them later on, they had more than enough other colonised areas that were colonised to make us of and maintain good relations with for many decades or even centuries to come.
This plan ultimately failed to factor in wars in Europe tiring out their armed forces and capacity to maintain their empire but even then the fallback of alliance with said nations remains overall.
This agenda meant that not for reasons of morality but of expedience, it was suboptimal to overly bully the culture that was in place and instead what they'd do was find rivalries where they could help one side that wasn't currently 'winning' to win the power struggle and then say 'now you owe us, help us stay in control here'.
This tactic worked most places but the native tribes had zero interest in ruling over the area such as Canada or the US, they just kept to themselves. This meant that the British (who, as you said, came after the Italians, Spanish and Portuguese had already begun a lot of colonising in the Carribean and everywhere South of Us and in South America and what the Brits did was use their expertise to negotiate and 'tame' the Natives working out which tribes were more open to peaceful resolution and selectively being violent with the ones who were beyond negotiation.
The natives has a lot of reason to be brutal and beyond negotiation, given how Columbus' crew and the Spanish+Portuguese had been treating them. The Spanish and Portuguese style of colonising was to blackmail into their religion and language, totaly and utterly redefining the culture. They had to wipe out many tribes before the others caved in out of fear.
You can say whatever you want, these are the facts. This style of colonising was by no means at all more merciful than the British style, it was just more bare and honest. The British colonists were very good at appearing to be reasonable while actually being dictatorial but the Spanish colonists were just plain dictatorial. In fact, the only reason elections and democracy got introduced to Latin America is because they saw the success that the British and French had inspired in Canada as well as what both them and the Italians and Irish (as well as some Germans and Scandinavians who joined later) had inspired in the US. When people can 'vote' (back then only white land owners could), it makes people less likely to rebel. Latin America had much less of a proportion of Caucasians (and caucasians who are portuguese and Spanish especially if they reproduced with natives, don't necessarily look entirely Caucasian) so they realised that in their cultures they couldn't limit democracy just to rich white land owners and had to open it up further, however bribery and blackmail were again far more commonplace and 'bare/honest' in Latin American 'democracy' than it was in the US.
There is a consistent pattern here, if you haven't noticed. I am not saying that if you caved in and agreed to be Christians and speak their language that they abused you, I'm saying they relentlessly abused you until you did so. Even then, you had to 'know your place' you never could rise anywhere near to the top as a true native but it is true to say that many natives don't like politics, they dislike the strict hierarchy in nations as their culture was much more egalitarian.