NEW YORK—Investors are weighing how big to go on U.S. technology stocks in the coming year, as pricier valuations, regulatory risks and a revival of the market’s beaten-down names threaten to dim their allure. A surge in technology and internet-related shares helped lift U.S. indexes to record highs this year. Gains in Apple, Amazon, and Microsoft alone accounted for more than half of the S&P 500’s 16.6 percent total return as of Dec. 16, according to Howard Silverblatt, senior index analyst at S&P Dow Jones Indices. Tech took a back seat in recent weeks, as hopes of a vaccine-led economic recovery fueled a rally in energy, financials, small caps, and other less-loved parts of the market. The Russell 1000 value index climbed 10 percent since breakthrough vaccine data was announced in early November, compared to a 4 percent gain in the Russell growth index, which is broadly populated by tech …