With tanks, bigger is almost always better (actually can't think when it's not better) more space generally reduces aggression, and can provide more hiding places. I don't think your stocking options are going to change much, and you probably won't get guarantees that you may not have challenges down the road, but if it's a new tank, and the all fish go in at once, it's probably the best option you will ever get to introduce roommates to your JD.