"CeeVee" seems to have a great time and he is in his teens now and has been playing for a while. Sure A2A is the toughest, but GVin is easer to get a kill in, bombers are again fairly easy to learn and become proficient in. So the game can appeal to a younger group and learning the easy stuff first can make it fun.
I think there are a few things that could make it work.
A real "free to play". A half dozen planes you can fly in the MA any time. Add in a couple tanks and let them in.
Price drop to $9.95. This matches most other subscription based products be it TV, movie channel and so on. It is what people are use to and dont seem to bat an eye to spending....as long as they dont use "Rocket Money" to track their spending

Get the word out there. With a new price and a F2P a steam relaunch might be a good idea. Pay a couple of game influencers to run a review of the game. Hit as many Social media sites as we can. In this we need as many people to work this. Your on a modeling page and someone post a P47 model they built, comment "Great Job! If you want to fly one in a good computer game check out Aces High!". I love posting on War Thunder adds on FB !

I dont post much at "redit" so they limit how many posts I can do, but everyone who has an account on any social media group can post as much as they can. Any word that gets out could help.
Aces High vs the others, I dont think the others can come close to what AH has.
Community, except for a few here and there this group is fun to play with, works well to help others, and even meets socially in person. You dont see that in many games today.
Game Play, this game may not have cockpit switches and a million and one "bindings" to promote "realism" But the depth of the game itself out shines the others. 24/7 continuous war in which you can play any of many parts. Tanking, bombers both heavy and light, A2G with medium and light bombers as well as fighters. Ships both big and small. There is strategic fighting to hurt the enemies supply, or just flat out smashing a grabbing to take bases and land away from the enemy. You have to take two or three of these other games together to make AH.
Graphics, I consider AH graphics "Good enough". Sure some of the other games have very nice and high polycount graphics so that while your sitting around doing nothing you can look at the pretty parts. AH on the other hand doesnt waste computing power for pretty parts. It uses its power in the game. Most maps cover 65.5K square miles of play. Live action on all parts of the map at all times. And when you are fighting another player with a closing speed over 600 mph you dont really have time to count rivets.
Events, How many historical events do these other games play out? AH has FSO 3 times a month, one or two scenarios each 4 weeks long, not to mention Monday Night Madness and that Combat night on the 4th friday of every month. Highly organized events well planned out in advance with dedicated players to run them.
VR, AH has one of the best setups for VR. Combined with the traditional view settings and makes for a good transition. The immersion is really great and with being over complicated compliments the game in stead of making it harder.
Ive played many of those other games. No I dont have more than a few hours in them.... heck it took a couple hours just to get enough bindings set to fly in DCS

But I never saw anything that could hold my attention as well as AH. Im sure we will have as much trouble convincing anyone playing those game that this one is better as much as they would have convincing us theirs is better. Well maybe "better" isnt the right word, fuller might cover it better. Get the word out there, post more videos. If you dont know how to make videos at least learn how to "share" videos.