There wouldn't be much point, we already have too many ships and too few reasons to use 90% of them. And what's a huge trade ship going to let us do right now? Do you feel like making money is so hard, that you need a way to make even more of it with a bigger ship? Either the Panther Clipper will be good at core mining and there will be no reason to use anything else, or it will not and there will be no reason to use it.
Before it makes any sense to add more huge ships, we need a full rebalance of the economy (so that money becomes a progression factor again) and the way big ships work (so that they become the specialized and expensive tools they were meant to be at first).