Net positive I suppose.
The British Empire spread the Protestant faith, the Protestant work-ethic, Anglo-Saxon respect for individual rights and limiting the power of rulers, across a wide swath of the world. Uncounted millions of people will be going to Heaven who would otherwise have gone to Hell.
On a more personal note - some of my own ancestors were apparently dirt-poor people who got a whole new start by moving out to the Colonies. The wise apple curses not the tree.
The Spanish Empire, on the other hand, spread the culture of 17th-century Spain across much of the world. A form of Christianity in which the gospel was obfuscated by superstition and ritual. A cruel philosophy of government.
The legacy of the conquistador is the mindset that wealth and prosperity are things to be gained by robbery and violence. Wealth is something other people just somehow have, and if you want it you need to take it from them.
When I look at the American Democrat party's new little mascot, AOC with her too-wide donkey-face grin, and consider her proposed policies in the light of history, I say: "Well, you would think like that, wouldn't you, little miss Cortez! Found some new Cities of Gold to plunder, have you?"
(In the long run the Spanish wrecked their own economy, and that of many other Old World nations, with the glut of silver they imported across the Atlantic. But that's another story.)
Even the Pinochet-fanboyism we sometimes indulge in on this forum, ironically of course, creeps me out on a certain level. It's the values and mindset of the Latinosphere seeping in and polluting the Anglosphere.