Was the British colonization of India a force for evil or was it a force for good?

Northern Ireland (importing Protestant Scots ... why?)

South Africa (1st concentration camps to contain Boers in 2nd war)

India (salt tax, EIC financing local wars using revenue from the Bengal Presidency, buying Indian cotton--preventing textile industry in India--selling finished cloth back to India, administrating Muslim, Hindu, and Sikh populations in the same colony)

China (importing opium from India - - only Communists fixed problem by executing addicts)

Australia/United States (used to dump unwanted Brits, handing out smallpox-ridden blankets to Native Americans)

Africa (like India ... administrating hostile tribes into same colony & buying raw products--selling finished products to colony, pivotal actor in the 'Scramble for Africa')

Trading allegiance for support for both the state of Israel AND Palestine at the same time (1915)

Anglicizing strategic locations (Gibraltar, Falklands, Singapore, Hong Kong, etc. to the consternation of nearby nations)

AND finally, why are there so many artifacts from other countries in British museums?

Good? Hmm ... the only thing I can think of is positive byproducts (modernization or military/economic assistance today, mediation in political conflicts) of the damage caused in the past.

Now, many of the evils perpetuated upon the world by Great Britain have been copied, or initiated by others (Imperial China, France, Spain, Portugal, the Netherlands, Italy, Germany, Russia, Ottomans, Austro-Hungaria, United States, Japan, Communist China, etc.)