Most of the players of the airlines I listed in my post were new players or playing AS for less than a year when they started their successful airlines. Success does not come overnight. But there is one difference between the "two groups" of players (let's just call them two groups). The first group is polite and wants to learn, and appreciates guidance. I have received my fair share of guidance here, and I also have expressed certain level of frustration of somehow not understanding the mechanics (especially of ORS) in the beginning.
When you show willingness to listen, you will be helped by more experienced players. If they see you helping others with the little knowledge you have, they will be even more willing to help you. There were several threads here of players offering themselves as mentors. Few have taken the advantage of these generous offers. But when you come with an agenda, and when you do nothing else than complain, very few would be willing to help out. You will find yourself isolated more and more, as others (experienced players) will not want to deal with you.
Show a little humbleness and willingness to learn and listen, and take advise to the heart, and you will see completely new horizons opening up for you. Be a d**k (sorry for the word but I use it intentionally to make a point) and you will not go far.
I will still address some of the issues you mentioned, because I have an opposing view.
Using cheap old planes is not an exploit when you start on an old server. It is a way to build a competing network. Whether such network will be competitive will depend on other factors of your strategy. Anybody can do that, with 25,000 AS$ a week 26-year old 737-300s. But you must know what you are doing, and you must compensate for lower image by better service or seats, thus your profit margin will be lower, but your lease will be lower as well. You must know where to put those aircraft and you must schedule waves to get connecting pax right from the beginning.
Better seats are not exploits, they are what they are - better seats, better product. You have Ryanair and you have Etihad, both offering flights with different concept. Of course Etihad will have a better rating. Or just take Turkish, on Europe to Turkey routes. Comparing Turkish to Easyjet is like comparing Standard Economy to Comfort Plus seat in AS. Different product, different image, different price. Better seats will give you better rating, but lower profit margin if you use the default price. You can raise the price but that in turn lowers the rating. Finding the sweet, optimum point is the challenge, and when you find it (for each seat type, route, aircraft, etc.) you have a 50% assured profitability (the other 50% is optimized network). Each part of AS (aircraft, product, seat, price, image, network) performs a vital part. If you do not develop your strategy as a little guy, if you do not find your own "mix" of these features for your airline, you will have no luck as big airline either.
But all of this takes time, the time you better spend researching on the gameworld than complaining on the board. I spent countless hours on research (yes, research is important) and that did bear fruits, lots of fruits.
It’s about attitude ... you can either see the glass half full or half empty. You can either see a slot congestion, or an opportunity to awaken the sleeping giant. Azul Linhas Aereas became the 3rd largest airline in Brazil by finding its niche and serving routes nobody ever thought of serving, creating a hub in a place nobody thought to be a viable hub place. Neeleman does not have luck, he has brains. What Azul did in real life you can do in-game in AS.
But that brings me back to the beginning ... listening and learning, or complaining. Yours is the path to choose.
P.S. IL-planes on Quimby... My opinion is that those who use them only want to stroke their egos. Why they would do it on a sandbox, 3-month duration server, is beyond my understanding. I think most of these people would most likely not be able to build a large-size airline on an existing server and sustain it in a long term.
But Quimby is a sandbox, so anything goes.