By Jennifer Piacenti Bets and analysis for Friday’s Astros-Royals, Padres-Brewers and Mets-Dodgers games. Time to head into the weekend with our MLB bets! We are off to a 21-13 start to the season at SI Sportsbook and 18 of those wins paid plus-money. If you’re just starting to follow my MLB bets series, I try to only pick plus-money bets or bets with little juice. Our bankroll strategy is for wins to pay more than we invested. Sometimes that means the “risk” is higher, but so far our bankroll is very healthy. You can also track my bets across all sports on Sharprank, an independent ranking sy…