I know a few single expat teachers working in Kowloon Tong living in dense Kowloon near the MTR Lines, living by their own or sharing places. Commuting to HK Island is super easy. You can take a cross harbor bus or minibus to Kowloon and change a taxi in mid night or get off at TST East, Hung Hom near the tunnel, Jordan, YMT and Mongkok Nathan Road. Not expensive compared to the UK or the US. A cheap option is Lamma Island but it will involve ferries from Central. Sai Kung/Clearwater Bay will be good if you like the enviorment there.
Kowloon is mainly an Asian area, in addition to Chinese there are Japanese, Koreans, Thais and South Asians etc. With fewer western residents than HK Island except the tourists.