Slapping additional engines to our jets is all fun and what not, but now the landing time takes so much time that it's not worth it. Adding "braking force" research would make jets slow down faster and make them way more fun to control

double that, drag chutes maybe?

The engine doesn't support changing braking force without scripts, so this is not high on my priority list. It would be easier to add new vehicle types with higher braking values. Maybe there is a way to give quality aircraft higher braking speed, but I haven't looking into how modding quality works.

Ah yes, quality would be a great middle ground.

I've looked at how quality works, and it seems that the way quality affects entities is hardcoded to only affect health and equipment grid size, so the quality idea is out. Another idea is to take an idea from Xeraster to move this mod's high end aircraft earlier in the tech tree.https://mods.factorio.com/mod/Aircraft-space-age/discussion/6727f5f0aae1c8e18e9998a7

By doing this, there would be room in the tech tree for new aircraft that require carbon fiber, which would be lighter but less durable than steel aircraft. Changing weight allows aircraft to fly faster while braking to a stop in the same amount of time.