Yes, you can completely change formations and such. After these first two rounds you have unlimited trades, which means you can go to anything you want.
And just because, here were some of the high point getters from the first round of group play.
8
-Arwen MF
-Mardil MF
-Narvi MF
-Eldacar MF
7
**Miriel FW
**Gandalf DF
**Durin’s Bane MF
*Sauron FW
*Ar Pharazon FW
*Isildur FW
*Khamul DF
*Finwe FW
*Eonwe FW
-Tar Palantir FW
-Indis DF
-Nerdanel FW
6
**Melkor MF
*Elros GK
*Finarfin MF
-Elrohir MF
-Earendil MF
-Sangahyando MF
-Balrog #4 MF