My current house was wrecked to pieces, so showing would not be of any help, but I found a concept that makes my bases feel a lot better than the default boxes we all do sometimes.
I try to find mountains, and carve a stairway from the bottom to the top, but taking turns for every floors, so that it's not a strait line.
From that, I dig tunnels to various outside areas, also trying to avoid the strait path.
When needed, I can put rooms on the floor I want, because mountains have a lot of space, and even the ones that are rectangular usually feel better than the standard cobble squares.
Add in some wooden (or other materials) supports, and ty to put out cobble/dirt/gravel from the walls, putting smooth stone and various bricks instead.
I am by no mean a great builder, so that's how I found to make some decent bases that still fit my machines.
If you make your tunnelswide/high enough, you can also put visible piping for fluids or items, if that fits what you want your base to look like.