Question about Pax per route

reduce prices, and i think alliences and hubs play a big role too

It is a supply and demand calculation. If more demand than supply, the higher price works. Of course, since a flight cost is set, filling a flight is the most profit. spending less flights on a higher price would be the most profitable. I think keeping the supply an amount less than demand, eliminating the cost to supply, gives a higher profit margin but idle aircraft are an expense, too.

You could min-max the prices and flights for 10 minutes per route to maybe earn an extra 20k or so from each flight...

...or you can open another route and earn 200k.

Hubs and alliance hubs would help increase demand for those seats, though.

I don't think it is an easy this is better than that choice. It is all about optimisation.

For me, this is the first thing to get right is the number of aircraft deployed on a particular city-pair. All else being equal, on a high volume route, which likely has high gate costs and landing fees, then minimising flights is a good thing, i.e. bigger planes. But, on a low-volume, low-cost, one more flights helps your reputation score, therefore smaller planes. And, you should be conscious of not adding so many aircraft that you trigger the need for an extra gate to handle a few extra flights.

Now is the time to think about optimising price vs load. This is more easily judged: just look at the daily profit! My approach is to maximise load (making best use of capacity) and then, if my capacity is equal to demand on a contested route, play with price.

If capacity > demand and load < 100%, reduce the price until load equals 100%. If DOP for this combination is less than DOP for default prices, revert to default.

Oh, and don't forget that your aircraft might be more profitably deployed on an entirely different route. Decisions, decisions.

Optimization strategy must include player time or it's woefully incomplete. The calculation you describe may work with a small airline for which one can continuously adjust route pricing; for a larger airline it doesn't.

You have to think about which is the bottleneck resource to overall profit: player time or aircraft. In the very early stages of the game when planes are scarce, it may make sense to set route density below default carrying capacity and price routes individually. Later, once your order book is full and planes are streaming in, that strategy is suboptimal unless you have unlimited time. 

My strategy is specifically geared to allow me to deploy a hundred planes in a few minutes. Even though I do so at a sub-optimal profit rate relative to the theoretical - absent time constraints - that strategy enables me to remain the undefeated, unquestionable Emperor of AE. 

I see your point about optimising player-time, but I think of it as a separate matter.

I often come across routes that are priced at twice the default and have to believe that increases profit.