I have to agree with Nick. If I as a bowler received this as an email, I'd tell you to go blow yourself. I know (and I expect that your bowlers do to) what are my strengths and weaknesses, and telling your opening bowlers to bowl cross seam with a new ball is the biggest pile of poo.
Your bowlers are supposed to be good enough to bowl accurately first ball. Warm up in the nets for fifteen minutes beforehand - absolutely, but as a batsman, if you received a ball that pitched on a good length and then seamed/swung away from/in to you first ball, you'd not have a clue what to do, and that creates more uncertainty than a straight yorker.
I think you are worrying overtly about what has happened, and if you really want to help the team out, arrange net sessions where the bowlers can practise what they do best, and you can help them by batting, then encourage them to have a plan in those nets sessions and to keep up their good level of performance. It worked well last season, so what's really changed?
Otherwise you run the risk of being ridiculed and told where to go very rapidly