I decided to check out your map. Here are some things that I noticed.
Blue players can open this door at one of the red forward spawns. I don't think I need to explain why this isn't good. Make sure to double check all of the door logic in the map.
This hole can be shot through. This is bad because it has the potential to eat soldiers' rockets and demos grenades mid battle. I would either remove the hole or prevent it from being shot through with a block bullets brush.
View: https://www.youtube.com/watch?v=tR_4Oe5AnC0
. The map lacks a lot of clipping in general. I would recommend watching that video to get a better idea of what I'm talking about.
Some brighter lighting could also benefit the map. Even the darker maps in TF2 like halloween maps are still pretty bright because too dark of lighting makes it hard for players to recognize teammates and navigate the map in general.
I also think that some of the scaling is awkward. Some of the rooms are really clostrophobic for a TF2 map. Here are some examples of what I mean:
Also I'm not sure why there is a spawn here with no door or anything. Demos and soldiers can easily camp this:
Overall, the button idea seems cool, and I hope you continue your mapping journey!