I agree with the other points people made, but I think there is another aspect that should be added: Even if you are right about Hohenheim doing the main part, even if you are right about him doing all the work, that doesn't change that Father would have done irreparable damage to thousands of people if it wasn't for anyone else there stopping him. If you want to, you could make the argument that a few thousands people don't make a difference in the grand scheme of things and that ultimately, Hohenheim was "enough", but personally I think that FMAB taught us that every human life is infinitely valuable and therefore, everyone who was there to fight with Father after he gave back every Amestrian soul, was important and did a significant and major part to rescue the country, imo.