Texture Pack Help

Firstly, I apologize if this is the wrong place to post this question, I am new to this website but I do not know of any other place to post my question and get a response anytime soon. I am making a server and need the spawn area to be outside of the map, but the map needs to have a world border. So my plan is to create the spawn outside of the world border and then teleport the players inside/outside of spawn. Firstly, is there any obvious problems with this plan such as the players not being able to spawn there because its outside of the world border or something? Secondly, when you're outside of the world border it gives a red blur around the screen. I don't want this since people are going to be outside of the border anytime at spawn so is there a way to delete this out of the server texture pack so players will not have this blur as long as they have the texture pack? Thanks in advance! :D