We think there could be advantages to deciding 2nd so last night (we go through turn 5)
we decided to choose secretly and reveal at the same time, using a d6, if it was a 6 when you removed your hand you had committed your commander.
I could see where the active player could declare first, I mean perhaps in reality, as the active player committing to charge the other player would see you riding ahead of your troops and then decide if he would so inspire or lead from the rear.
On shifting we said a battle line could not because in the examples it only used BG and we thought that perhaps that was too complex to do, but we didn't find a definite yes you could or no you could not in the rules.
This is my 2nd game, but the first one we did a bunch wrong so I still feel like its my first as well, Plains and I are having a blast, we surely appreciate the help and I might add very quick help many times on the forum.
we do have the players index (which is awesome) and the faq as well.
Steve