[Hertston]

Developing a couple of competitive low level tourney squads will generate far more revenue through packs and cards won than anything you can do through the ladders. Unless you are extraordinarily unlucky, anyway. Experiment with open, live, non-live and capped tourneys to see where you have most success.

The easiest way to fix a roster without time pressure is to first run one filled with anything eligible that you have. When you get eliminated, you can open it up from your tourney list with full access to the roster you used through 'RosterManagement' for as long as you like. Once you have changed it to what you want, set batting orders and so on, 'submit' it and save the roster via the import/export tab. Enter another tourney of the same type, and it should be there; if not just import the save. Saving is also useful if you make changes that are unsuccessful so you can easily revert to what you had before; just name the files appropriately.

BTW, although the usual reason for tournament rosters being reset is MLB live cards that change value as Leo says, it's not the only one. You can still sell cards used in an active tournament, but the roster will reset once it ends. I've also had them reset for no apparent reason and I don't use live cards in tournaments at all. Always pays to save and check on occasion!