Seriously, if you are so entitled to spend 5 millions on each novus if you are going for more than one, go ahead and do it. But it's absolutely NOT needed. My point was that Novus only requires 2 things:

1 - Doing a daily expert roulette (+daily hunts though we still don't know how this will work).

2 - Spending gil on materia.

2.3 will make even alexandrites more available and accessible, which in turn could potentially and understandably encourage those that already have a Novus to go for another one (maybe at a slower pace) since you'll be stacking alexandrites with the daily roulette anyway and it will NOT cost you anything other than doing the silly maps.
The problem here is that there is a massive brick wall called Atma quest + 9 books which discourages even the slightest thought to go for a second Novus despite having the possibility to stack alexandrites and gather some materia with very little effort after your first novus.