Does anyone else find that 30-minute lessons aren't long enough?!?!
Yeah I did, although they were short-lived anyway.
Far worse imo was the frequency. I thought once a week was either too often or not often enough, depending how you looked at it.
A week wasn't long enough for me to feel I'd made progress by myself, so I went to most lessons thinking "There's not much point, I know what's still wrong and I can't play the piece yet" So it was 30 minutes of being told what I can read here and / or hear for myself.
Worse, in the short time I often played far worse than I could, and they'd drag something else out of the cupboard, perhaps a wrong note that I'd played 100+ times at home without ever making a mistake. So they'd say "practise this, this week" and I'd be thinking "but I haven't finished what you told me to practise last week yet and that mistake was your different piano, you being sat there, me trying to focus on what you just said 5 minutes ago about relaxing" In other words, 30 minutes wasn't long enough for me to learn to play for the teacher.
OTOH it was too long to more or less practise the piece with them lesson by lesson until the penny dropped. They didn't think about teaching in those terms anyway. It was clear they were trying to "cover stuff for a week" focussing on how much time there was until the next lesson rather than how long the lesson was.
If I had lessons again it'd be either an informal hour or three, every few months, so I could go and play, knowing at least it's pieces I feel I can play as well as I can possibly get them without someone's input. They can then demolish them

and tell me where I'm going wrong. Rather than me playing something I know I can improve by myself and them picking a random fault and deciding that's this week's thing.
Or daily, so it's focussed bar by bar on a piece.
I think you'd probably get away with 30 minutes or less on the latter.
I guess I'm saying that for 30-45 minute lessons, aimed at a beginner, in my experience, forget the length of time in between in the "I've got to give them stuff for a week" sense, and "they have everything to learn, this and this and this" and work as though they are coming in every day. You'll probably be less rushed to cover stuff. It'll be slow progress, but probably better than what you note is the standard "a tenner for 30 minute weekly lessons" teaching approach.
It might be true that for a longer lesson you can do them weekly, I've no experience. Perhaps, had I played for an hour some of the difference between how I could play the piece at home and how I played sat next to someone in a 30 minute lesson might have been eroded, so it would have given her a better indication of how well I could play the piece and what I really needed to practise to get it better rather than whatever random mistake I made.