There has been many discussions going on over different strategies on how to end up on the top spot in valuation. Many discussions pointed towards the fact that at the end of the day the whole point was to "go big or go home" as bottomline the more passengers you have, the more profit you make as long as your margin is positive.
Nevertheless, while building an airline with thousands of planes it might still not be evident on what exactly large spamlines do to end up on the top of the ranking in valuation. Also for those that once are there, the lack of competition makes the game less intersting from the perspective that if in a world where you have about 200 or 300 airlines you end up competing always against the same top 10 or top 20, the game loses part of its challenge as the remaining 90% of the airlines are not competitive enought.
This post is not directed for those who are building airlines that pretend to look real but for those who would like to understand the tactics that spamlines use and at least have all the information they need to compete with them if they wish. At the end of the day it can all be summarized in some tips that proved to work and that would allow any airline to remain financially competitive and prevent them from having to bankrupt. While The Flying Cow "helps bots to bankrupt their airlines :)" , it would also be nice to make all the worlds more competitive because, as others pointed, otherwise it becomes too boring.
Thus, here's the short list of simple observations on what can be done to boost valuation:
1) Planes: For the same amount of passengers, when choosing an engine or a plane choose the one with the lowest fuel flow. Good examples are CL-44 Yukon or Tu-114. If you ever plan to fly routes longer than 500 miles you should care about it. Regarding seating, just go all Y seats as sooner or later spamlines will do, and that would be always much more profitable than having any other type of seats on the plane plus time wise you would only need to care about filling 1 type of seats when updating/reviewing routes.
2) Scam IFS: Min quality and Max prices for everything. Same with in-flight entertainment. 1 TV screen to be able to put ads every minute and charge max price for use.
3) Routes lenght: Schedule first routes below 500 miles (use the filters when browsing airports). Profitability of the route decreases with its lenght (talking about connecting PAX, as those don't care how many competitors you have on a route, they are "magic"
4) Hubs: Open hubs in every airport you fly - you gonna use the connecting PAX (blue bar) to make money on them by charging ridiculously high prices. You gonna get 50% of that rediculously high price which will be always way more that you would ever make with "green bar" passengers. Connectig PAX do not care how many competitors you have on the route.
5) How many seats to allocate: As a reference you can allocate up to 10 times the seats that you see as "route demand" (green bar). It will mainly depend on how many planes you have. Bottomline - when allocating 10 times more seats than needed you can still charge connecting passengers around $1 per mile and fill the "blue bar" of connecting passengers (e.g. for a route of 400 miles charging $400, from which you'll end up getting $200 as connecting PAX only pay 50% of the fare). This is how you can get operating profit beyond $10B on a route... and way beyond
6) Pricing: directly depends on how many seats you allocated. If you allocate 3 times the seats needed, ticket price = miles x 4, if you allocate 10 times the seats needed, ticket price = miles x 1. Find the sweet spot where you gonna fill the blue bar. You wanna max the profitability per plane (you can see it in "plane details").
7) Small airports: given how route prices are updated, you wanna go first to airports that others might forget about. Why? Because whenever a new airline joins a route and sets a price the filling of the planes is recalculated and you don't want to be updating prices over and over again. Go to airports in the middle of nowhere and just start opening hubs and scheduling routes with other small airports with insane prices and a tonn of available seats that connecting passengers will end up paying anyway. You would only need to care about those routes if someone also goes there and starts opening routes (as filling of planes will be recalculated and you will need to update the route, see point below).
8) Updating route prices: if everything mentioned before done properly - even in the event that someone joins your route and your fill rate for the route drops, just open it and click on "save" to "magically" fill the blue bar again. Somehow your connecting passengers will return and you will happily made insane amout of $ because, basically, they are magic
Disclaimer: This observations are made for educative purposes only and seeking to ensure that all the players are on the same page and have the same means to compete with other airlines if they want for achieving top valuation. By increasing competition the game would become more exciting and make it less boring for those sitting on the top spots in the rankins while waiting the world to end (e.g. myself in R1 or R5).
Any correction, further elaboration or comments are welcome