For the sake of transparency here are how some of the things were chosen.
First, there were threads like this one by Soldier
Timewasting Places that have a ton of places that bother him and other people in maps. And there are more threads than this one.
Secondly, we have an internal list of things that need to be fixed in some way for maps. Some of these were added by me, some were added by other developers from their experiences, some were added based off of community feedback.
Here are the stuff for Death Star. #24-25 were added to the list before I came back from retirement. #26-28 were added by me. #26 was something I forgot to fix for years. #28 was after a thread on this forum that prompted me to check out if we ever added that flag. #27 is a combination of thread in forum, in game suggestions, and my personal wants. It is also too big of a change to do quickly. #29 was added most recently by Defiant after the most recent patch.
Now on Death Star I did some of the changes fairly quickly due to time constraints and I am willing to revisit and make more permanent and better solutions to them that work for both allowing mandalorians some good spots while also making it impossible for them to have stupid amounts of cover that they cant be flushed out from.
Then why would he add a ship in DoTF if he removed catwalk because of timewasting.
Level of timewasting/camping on catwalk and ship are no where near equivalent. I wanted to add the verticality that catwalk provided which was good for several situations such as rocket arcs, add more cover to hangar to reduce some sight/firing lines, etc. The whole purpose of the ship is to be similar to catwalk but not have the camping benefits where it so high up that only jedi/sith and mando can reach without the elevator and having more entry points for those other classes (3 instead of 1). There really isnt a "timewasting" problem with the ship. There will always be a camping problem but camping and timewasting arent exactly the same thing.