The issue with this being removed is much what alot of people above say.
Set messages are useful for when your needing to chase someone down or tell them to stop.
i have 2 Set messages that i use on my GRP, one announces my officer and they are part of the GRP and the second ask's them to cut engines. After that i will type depending on what they do or dont do.
The problem here again its been said is your punishing those who use it responsibly because of a few who decided not to.
Its hard enough trying to type out what can be considered a decent RP engagement when alot is already going on, wether thats trying to get a trader to stop, to engaging in a group fight. I cant tell you the amount of times ive nearly or have died because i was trying to make a decent engagement post just to make sure noone cried about me joining the battle.
All thats going to happen is your going to see MORE 2 line dialogues since not everyone can type at the speed of light and less interactions via pirates and potentially police because its easier not to try.