Yea, can definitely have multiple modes/strats, as long as they aren't exclusive to quali, etc.That is correct, but there are different modes, called strats, that can be used in testing and practices.
But no party mode that can be used in qualification and occasionally in the races.
Might be a little less of an issue with the current engines (except Alpine) as they seem pretty solid. Previously, Merc had a significant engine advantage.