Regarding Travel/Flight Feats and Reactions
If a character travels or flies very fast through a very empty terrain, in which it doesn't necessarily have to react to sudden obstacles, the speed in question is travel or flight speed, but not necessarily reaction speed. In order for it to also be reaction speed, and the speed in total hence applying to the character's combat speed, the character either must have demonstrated the ability to react to sudden obstacles while traveling at this speed, have a calculation made that supports the character having corresponding reaction speed/time or otherwise demonstrate having comparable reactions.
Simply being able to stop accurately at the target destination does typically not qualify, as it can be spotted from a large distance to make preparations to stop or the character could even slow down before reaching the destination, assuming we only know the average speed with which they moved.
The typical example of such cases of travel/flight speed that doesn't necessarily scale to reactions is space travel. As space is incredibly empty there are virtually no objects one has to navigate around between destinations. Just flying in a straight line from A to B would be safe. At the same time the typical destinations, such as stars and planets, are so large that they can easily be seen from millions of kilometers away. As a result a character would only need reactions equal to a miniscule fraction of their travel speed to perform a safe and precise landing on them.