From Release notes from pioneer: link to original post

We hope you will enjoy this summer release, bringing several major additions, most notably a total visual overhaul of the Sinonatrix, a total rebalance of cost and maneuverability for all ships, and systems now filled with merchants, busily making their way to their places of commerce, making pioneer a little less "lonely". As usual, we have made many tweaks and other additions, and hopefully more bugs fixed than new ones introduced.

Major Changes and New Features:

• New ship model: the OPLI Sinonatrix has received an all-new hull courtesy of Nozmajner. This model rework is the first of a series of visual improvements coming to Pioneer, and paves the way for a new ship workflow tailored towards generating much higher-quality content! (#5106)
• Completely rebalanced acceleration, thrust, and price across all ships, and rework many ships' cargo and fuel capacities to have more coherent and physically-informed values. (#4970)
• Improved rendering quality: ship models no longer display spotty white lines at seams, and should now appear crack-free. (#5157)
• Added a custom mission and content related to the Rondel system... you'll have to find it for yourself in-game! (#5095)
• Add music to the map view and add several new music tracks (#5093)
• Add many more tradeships to in-system traffic and improve their behavior (#4984)
• Highly improved performance with many ships in one system (#5166)
• Cargo missions allow negotiating cargo amount with mission giver (#5164)
• Selecting systems by moving around in the Sector Map is now much more reliable (#5227)

Notable Bug Fixes and Minor Changes:

• Fixed GasGiant and other large planets 'clipping' out of view when seen from far away (#5157)
• Fixed a crash when loading invalid AI command data from savefiles (#5167)
• Fix a bug preventing the player from selecting stars with the same name in sector map search (#5193)
• Fix news event not significantly changing stock and price on the commodity market (#5192)
• Upgrade Pioneer source code to C++17 (#5151)
• Improved warm startup times by multi-threading some asset loading (#4951)

As always, the full list of features, changes, and fixes can be found in Changelog.txt.