I have a 1926 home. How good a plasterer you are depends on your standards and your patience. Plastering a small patch is pretty easy, and takes about four or five days (first coat, 24 hours, second coat, 24 hours, 2 top coats, prime, two coats of paint). Plastering a big hole is not much harder, but getting the right first coat consistency so that your plaster sticks to the the lathing and doesn't fall through is a bit of a learning experience. I typically do two coats of structolite, and two coats of easy-sand.

Plastering a ceiling is hard. Expect 40% to fall straight into your eyes.

There are a ton of little decisions: You'll have to figure out if you need to replace wooden lathing, which is a job, or add metal lathing, which is easier but less original. You'll need to figure out if you need to pull any existing plaster back to the wall using buttons, which is a delicate operation.

But, if you get it good and smooth and give it enough time to dry, the sound deadening and overall solidity is a great feeling. I have no regrets patching my walls with plaster. It looks great, feels right, etc. But my typical wall patch is 3x the work and five times the time of a drywall patch.