Even a century or two later merchantmen usually carried an odd mix of whatever guns were cheap – one wreck had guns from something like four different countries on board so each gun had its own shot gauge to sort out what balls to use with it. Even during the Napoleonic wars a ship of the line would not have had a uniform armament – generally with a different calibre of gun on each gun deck though if I remember correctly the British tended to move towards the lighter, faster firing 24 pounder as opposed to the traditional 32 pounder on the lower deck of a three decker. Then of course there were Carronades, the sawn off shotgun of naval gunnery.

Another big advantage of the English guns against the Armada was the mounts, they were easier and quicker to reload than the Spanish guns.

I don’t remember exactly the background of their rate of fire – I read about this topic several years ago.

There are two usual suspects;
- better conditions/training for reloading & moving the gun back into position (it moved back due to recoil).
- better thermal capacity and cooling of the gun (avoiding cook-off – guns at that time could fire less than 200 shots on a land battle day).

IIRC it was the latter, the first one doesn’t provide as much room for superiority.

The English used a firepower-centric tactic in the channel battles while the Spanish wanted to melee (they had additional army troops on board anyway). That’s why the guns became relevant at all – guns were rarely the decisive element in earlier naval battles.
I recall one or two battles which ended in the 16th century when captains became too shocked at one ship blowing up during a firefight.
Guns very rarely had sunk any ships till that century, everyone was used to boarding with a single previous salvo.

The battle of Lepanto was very much influences by a type of heavy galley with strong gun armament – something the Ottomans were not used to. That battle happened in the 1570’s and the Spanish + allies had won.

The range is not all that impressive and they do not state how accurate the long range fire is or if the gun able to fire a bigger powder charge. Short of advances in gun powder they could either make the ball lighter or give it a bigger charge or both. Cannons of every shape and size had already been invented by then. Accuracy was far more important at extended range, not that it really mattered in a fleet action.

It was overall a modern gun – but I doubt that it was used on the majority of the English fleet that fought the Armada – the English fleet consisted mostly of civilian ships (Galleons) that were armed for self-defense or piracy overseas.
It’s not reasonable to expect that they ditched all their decades-old guns in favor of a standardized design.