I agree with you. This is very fair, the one who enters the project at the first stage receives exclusive bonuses.
yes, because like that most projects from the beginning also investor in the beginning will get a bigger bonus and those who participate at the end of the price will be a little more expensive and sometimes there is no bonus at all so that is not a problem in my view, because everything has a disadvantage
Still, if we assume that the project is promising, all other things being equal, investing in the first stage with the maximum bonus is most beneficial.