It'll be hard to get people to give up their most profitable trade routes due to the way the economy works. But I will say you can do MUCH better than 2.5 mill/hour. My current route is right at 8 mill/hour.
But what ship are you running? That makes a big difference.
A one jump, two station route usually takes 8-10 minutes to completely and should net at least 4K per ton, per loop. That comes out to ~24K per ton, per loop, per hour. If he only has 100T of cargo space in his Type-6 then he is only going to be making approximately 2.4M an hour.
To OP, as for trade routes, you should be looking for a route that you can complete in 10 minutes and make ~4K per ton, per loop on. Once you start getting into larger ships you can be a bit lax on the amount per ton. For example I carry 448T in my trade Conda. I'm only making 3.8K per ton, per loop. But I can make the loop in under 10 minutes and end up making roughly 11M an hour.
Now from the sounds of it your route is profitable. Some extra advice though, multipurpose ships are better at trading than trade ships.
Type-6 100T vs. ASP 120T
Type-7 ~200T vs. Clipper 232T vs. Python 272T
The only one that can carry more is the Type-9 with 500T vs. Anaconda with 448T. But in every example the multi-purpose ships are better haulers since the can defend themselves and generally are not easy targets in comparison to their transport counterparts.
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