Did the US rename Alaskan villages/towns/posts after purchasing Alaska from Russia?

Well, the United States has definitely renamed one Alaskan town. It was also the only Alaskan town – Novo-Archangelsk, today known as Sitka.

was there any backlash from the people?

At the time of The Purchase, Alaska contained about 2,500 Russians and those of mixed race (that is, a Russian father and native mother), 8,000 indigenous people, and possibly 50,000 Inuit and Alaska Natives living outside its jurisdiction of the Russian-American Company.

After the transfer, a number of Russian citizens remained in Sitka, but nearly all of them very soon decided to return to Russia, which was still possible at the expense of the Russian-American Company. By 1873, Sitka's population had declined from about 2,500 to a few hundred. After the Purchase of Alaska, the Russian language quickly went out of use in almost all settlements. Alaskan Creole population either switched to local languages or studied English.

I'm curious as to if there were forts or towns with previously Russian names that the Amercians renamed to sound more English.

Let's check. Russian Alaska was divided into five departments:

Sitka department, administrative center – Novo-Arkhangelsk (today known as Sitka);

Kodiak department, administrative center – Kodiak (today known as Kodiak);

Northern department, administrative center – Saint Michael Redoubt (today known as St. Michael);

Unalaska department, administrative center – Unalaska (today known as Unalaska);

Atka department, administrative center – Atka (today known as Atka);

As you can see, by 1867, most of the settlements adopted local names and not Russian.