Iso Booth Curved Ceiling

Hello, I am attempting to build an iso/ vocal booth in the loft of an old church. I want do this for under $1000. The space I have available is 7 feet wide by 8 feet deep. The ceiling is curved the height starts at 4.5 feet in the back and end up 8.5 feet where the entrance will be. My first question is - Is it a bad idea to build a vocal booth that has a curved ceiling? I have attached 3 photos for to give some more detail of what the space looks like and what I plan to do. PS - I hope I have supplied everything required.

Shayne - it doesn't look "curved" but it does appear to be angled or sloped. Either way it's a good idea to have an angled ceiling in a booth.

Thanks John - great site you have here! I've been looking at some of the posts on booth construction and I think I have enough info to start based on that. I will post picture as I go so others can learn from my experience. I do have a question about doors. I was planning on using two doors with an air space between them. Is this the best idea or do some people use only one doors? Thanks, Shayne