Good short fulfils two criteria: Price meets resistance. Price makes reversal pattern. Based on these criteria, shorting EURGBP is not a good bet. Member section (login required) with further elaboration below.
Want to know how to choose the right currency pair to trade? Realise first of all that currency pairs are different so there is no one-size-fits-all strategy. Sort them according to their level of volatility, their trading pattern and their performance then pick one according to your strategy and fits your psychology.