My first time flying a Tethys, I was expecting something like a scout ship with some mining capability. Such a ship would have been an excellent choice for making money while being capable of fleeing from combat. What I got was I tiny miner that flew like a god damn freighter. 
The medium class mining and transport ships were even worse. I had to slam the brakes 30km from the station so I wouldn't run into it and bounce off. Docking was a pain. 
Eventually, I got  myself a fancy combat ship. The Nemesis. Oh, don't  even get me started.  This thing flew like a goddamn  scout  ship. It flew even better than s-class fighters, which is ridiculous. I would  have happily paid the extra credits to get a mining ship with this kind of maneuverability. 

I made this mod to balance ship maneuverability more according to their size rather than their role. Medium mining ships shouldn't fly like fighters, but you don't have slam the brakes 30km away so you don't bump into the thing. The small miners and freighters, however, do perform like little fighters. They're tiny, why wouldn't they? Because they don't have 4 guns attached? Pfft.

The Nemesis. I can't stop using it. It's too good. I dumbed down it's movement slightly so it does feel like a medium class ship, but it's not a slug bug by any means. 

To install, extract into your extensions folder.

I haven't tested all the ships, and am very open to feedback.

Mods I can't live without:
RedXRedemption - https://www.nexusmods.com/x4foundations/mods/418
Expanded SectorsX2 - https://www.nexusmods.com/x4foundations/mods/417
X4 Sound Overhaul - https://www.nexusmods.com/x4foundations/mods/405
Fix Bail Logic - https://www.nexusmods.com/x4foundations/mods/87