If I were going to start, I would start on the ground outside which I think is often neglected. A Catholic church is not designed only for Sunday Mass. So much more goes on and too often a church is first designed for Sunday Mass and then everything else is figured out. A church building should (IMHO) be designed for the Easter Vigil. If that is done, everything else practically falls into place.
What is the first thing that takes place at the Easter Vigil? The blessing of the fire. In the design of your church where does this take place? Are you able to have a good fire going for the congregation to see or do you have to have a small fire burning in a hibachi that only a few people can gather around and enjoy? St. Sebastian has a small but serviceable plaza on front of the church building with a flower garden in the middle which is of course flowerless at the Easter Vigil. It is there that the Boy Scouts are able to get a decent fire going. Another parish has a round cement pad in the grass in front of the church that is used once a year, everyone gathering around though it might be wet and possibly snowy.
Then, if you are able to have the whole congregation join you out for the blessing of the fire, the next problem is getting them all inside for the singing of the Exultet. If you have two small doors squeezing you into the church it is going to take forever until the third “Christ our Light” is sung. We have three sets of doors in front without many steps to negotiate and they serve pretty well though even with that it takes a spell for everyone to get in.
In Europe the entrance doors to the church are sometimes set in a set of much larger doors so that on great occasion such as this or when there are processions, the front of the church can be opened to let large numbers of people move in and out on just such occasions.
That being said, front doors to churches are often unimpressive but there is a tradition wherein the front doors of the church were labeled “Porta Coeli” or the doors to heaven (the Mass being the closest thing on earth to heaven” and at times the door would be decorated in much the same way as the reredos of the high altar. The altar brought us to heaven, the doors brought us to the altar.
So there is where I would start.