Analyzing multiple metrics, the evidence favors an Away win with Rayo Vallecano. The head-to-head record shows a 60% win rate for the away side, while their attacking metric stands at 56% compared to Alaves' 44%. Additionally, the goals comparison (57% for away versus 43% for home) supports this outcome. However, caution is advised as the form metric shows a slight home advantage at 53% for Alaves. Overall, the alignment of h2h, attack and goals metrics gives an 80% confidence level in an Away win. The conservative approach keeps risk moderate given some conflicting signals from the Poisson and form metrics.