According to last news, milestones are going to give 0 points looking for disincentivise multiple accounts. The reality is that it is not going to work. Basically, A person with multiple accounts is going to do the daily and weekly missions of each one of his accounts, and it is not going to do any difference.
The real incentive for doing people to avoid the need of create several accounts is giving rewards proportionally (or exponentially) to the progress, so, missions that requires more effort (or money invested) should give more points than missions which didn't.
Mutiplier missions also allow to disincentivise multi account practice. It is because a multipliers give more points the more points you have. For example, a multipler x2 is going to give 1.000.000 points to 1.000.000 points account, but just 1.000 to 1.000 points account. So, it will be better to have one account with very much points, instead of several accounts with few points.
My final message is, don't take away the points that the milestones give, because among other things these are the main engine of the game. Instead of that, restructure the amount of points that each missions gives in such a way that, the more progress you have the more points you get, put new missions and put multipliers missions to incentivise the getting of very much points in one account.