Google’s move to restructure itself under a new holding company named Alphabet will help protect its core brand, gives greater independence for its riskier investments — such as driverless cars or human longevity — and also brings greater accountability and transparency in those investments, observers say. However, they caution that Sundar Pichai, Google’s 43-year-old new CEO elevated from his prior role as product chief, also has his job cut out for him. Pichai’s Google will continue to battle rivals at home, including Facebook and Apple, and globally, such as China’s Tencent. In addition, the new independence for Google’s non-Internet investments raises the bar for it to demonstrate results. As an Alphabet subsidiary, Google will retain the Internet products — including the search engine business, YouTube and Android — that formed about 90% of its $66 billion in revenues in 2014.…