I saw this question just as I was reading some mid nineteenth-century documents which directly address (part of) your question!

Dr. Joseph Workman, medical superintendent of the Provincial Lunatic Asylum in Toronto (situated in Canada West, at the time- later Ontario, c. 1867) wrote in his 1858 Report to the government. He was very particular about the nature of treatment at the time.

"Medicine is had recourse to as little as possible," he wrote, indicating that good doctors (of the insane) should "repose less confidence in the efficiency of drugs, and to rely more on the recuperative powers of nature, aided by generous diet, supporting beverages [alcohol therapy], pure air, moderate exercise, and uniform kindness and truth." Workman subscribed to the "moral theory" of insanity, which held that much of what caused insanity was environment, at times in concurrence with various physical causes. Thus, the cure was based more on providing a healthful environment than treating any physical ailment. Workman would not have denied the value of medicine in certain cases, however.

We would be more likely to "cringe" at the treatment which preceded Workman's era- that of "restraint," a quite literal restraining of the "lunatic" patient in a straightjacket or other restraining device. However, the Utica crib that was invented by famed alienist Amariah Brigham to avoid the use of chains might strike some as quite cringe-worthy, and it's worthy of note that this device was in use through the late nineteenth century; it is difficult to believe this was considered a form of non-restraint therapy.

Changes in the treatment of the insane began in the late nineteenth century, as cases of "incurable" illness were on the rise and asylums came to be criticized as custodial institutions with little inherent restorative value. The leading critics of the now-established "alienists" (who had formed a professional society of their own, the Association of Medical Superintendents of American Institutions for the Insane- from now on, AMSAII) were actually neurologists, who in the late 1870s began a salvo of attacks on members of AMSAII and their approach, most specifically in New York State. (It's worth mentioning that New York was the home of the Utica Asylum, namesake of Brigham's crib).

The most damning of the neurologists attacks were surprisingly not those which criticized the lack of actual, physiological theories of madness among AMSAII members, though neurologists such as William Hammond did hammer on this point. Rather, the most damaging critique employed by neurologists (members of the New York Neurological Society in particular) was their accusation that AMSAII members benefitted, and had always benefitted, from a "spoils system" of government patronage. This accusation of corruption left a decades-long legacy of investigations of American (and Canadian) asylums and had many superintendents defending themselves for years.

I'm running out of time here, but I'll end by suggesting further reading. In the early twentieth century, Workman's methods of environmental treatment were already largely a thing of the past (though a legacy of this sort of treatment remains in modern psychiatric theory). Instead of these methods, new surgical methods began to be practiced, including the infamous lobotomy, and finally the pharmacological solutions we see in practice today. I can't speak to the use of electric therapy, as it is something I have not studied in great detail as an historian of mid nineteenth-century asylum medicine. But I think you might find this and that other infamous twentieth-century practice of lobotomy far more "cringey" than much of what was practiced in the nineteenth century. You're far more likely to find the general condition of asylums in the nineteenth century unsatisfactory than the treatments. However, there are always exceptions, and if you want to read more about another radical surgical intervention, read up on Canada's own R.M. Bucke, penpal of Walt Whitman and originator of some rather questionable gynaecological interventions meant to cure insanity in his female patients.