Long BSP names could be a good method for discouraging people from loading the wrong level. For these levels, there's no connection back to the first level so you can safely rename the first BSP. I suggest naming it after this place: https://en.wikipedia.org/wiki/Taumatawhakatangihangakoauauotamateaturipukakapikimaungahoronukupokaiwhenuakitanatahu
These levels look like a good example of the kiddos getting ahold of the level editor (and texture editor), which there's absolutely nothing wrong with, just to be clear on that point. But it doesn't mean the resulting levels will be of release-caliber. But with that said:
@macanah: please, continue making levels. So what if these aren't good; I imagine future ones will be better. And if you enjoy it, then... One part I did like was the last room with the moving columns. I don't think I've seen this before in a boss fight, and it added an interesting dynamic.