Thanks! Yup, it will be "a hobby project" until, if ever, it gets some users and revenue. Then, have several servers, some load balancing and redundancy, uninterruptible power with a generator outdoors on a concrete slab, contact Cloudflair or some such and have them do what is needed, etc.
Just looked up SSL, reverse proxies, firewalls, etc. Okay.
If you're virtualized on your host, 2x HAProxy on top of OpenBSD utilizing carp. It's great fun to set up and run -- and once you have it running, it's stupid stable. Very little maintenance required.
You can do this with Linux & keepalived, as well.
I mean, your intuition is correct that "cloud" is mostly just a bunch of boring, standard computers running boring standard software and there isn't anything they do that you can't.
But at the same time, boring standard software is (by definition!) commoditized and if you're spinning up some new and interesting thing, it's only going to be differentiated by the parts that are not boring and standard. So put the boring standard stuff on a credit card and do the interesting stuff instead.