I've got an iMac and an iPhone 7+, and I just bought my first iPad, the new 11" iPad Pro (128gb). I've had the iPad for 2 days now and I'm not super excited about it. I think my biggest issue is that I don't really know what use case it's solving for me.
If I want to get stuff done, I use my iMac. When I want to just browse stuff, I use my phone. I just got it because I thought it would be cool to have around, but I find it a little hard to use because it's so big. Browsing the web is easier for sure and most things are easier to read. It's difficult to type on. Awkward to hold and find my wrists getting tired holding it up. I don't do any drawing or take any notes, so two of the most touted features aren't things I really take advantage of. I also tried sidecar which I thought would be an interesting feature, but there's latency and the image quality didn't seem great to be honest (I don't have any cable to try it over USB which I assume is the more correct way to use it).
I was hoping it would be a bit of a family device, but it doesn't support separate users, so there's no way to separate out messages, photos, contacts, etc (I assumed it did, but got it confused with tvOS that just added multi-user support).
I don't mean for this to be a criticism of the device, because it's a tool used for a job. I just don't seem to have a use for it. I'm hoping over time I start to see where the iPad can be beneficial over the iPhone.
OP, I feel your pain, I really do. Apple has mastered the art of creating FOMO for their customers, and my wallet has suffered for it over the years. I have been flip flopping back and forth between the iPad and the Mac ever since I joined the Apple ecosystem, though my last stint with the iPad Pro as my full time computer lasted several very enjoyable years.
I consider myself a more advanced user of both macOS and iPadOS, but every few years I seem to hit a brick wall with the iPad. The first time that happened to me was back in about 2013 or so, when I got my iPad Air 1. Not long after that iPad came out, the Air 2 was released, and it could run all the new multitasking features in iOS, while my Air 1 was struggling to handle them. I eventually got rid of it and switched back full time to a MacBook Pro. 2 or 3 years later, right when I was REALLY getting sick of the heat, fan noise, and poor performance of the MBP, the first iPad Pro models launched and I was like, "Ok, THIS is what I was waiting for." I bought one immediately and used iPad Pro exclusively for my personal computing from 2015 to 2020.
And it really was the computer I was waiting for all along. But then when the M1 Macs came out, they solved all of the Intel-related problems I had with the old Macs, and they had the capability of filling in the blanks with iOS compatibility if I had an iPad app I really needed to use (yes, I realize this isn't quite a perfect solution yet). Compared to the current design and performance of just the base model M1 MBA, the 12.9" 2020 iPad Pro I was using with Magic Keyboard started seeming like a big fat heavy brick that was hard to open while laying flat and didn't hold a candle to the new Macs as far as speed, battery life, and power.
I will say this--I really do enjoy the Apple ecosystem better when I have every piece in play: Watch, iPhone, HomePod, iPad, Mac, Apple TV, CarPlay, etc. Having the complete setup from top to bottom makes it a much more enjoyable place to live. That being said, when I recently sold the 12.9" iPad Pro mentioned above and switched to MacBook Air, I reformatted and re-set up my old iPad mini just for reading, watching TV in bed, etc. It still does fine for those tasks, and is a little better than my iPhone in those situations. But I can count on one hand how many times I've picked it up to actually do those things. More often than not I reach for my 12 Pro Max instead.
The iPad is probably my third favorite device Apple has ever made, only behind the iPhone and Apple Watch. I get immense satisfaction from doing big, professional grade projects on a thin, light, powerful, portable tablet, and then using that same tablet to watch TV later in the day or read a magazine. It's just that I have progressed enough in the usage of my current stable of software that the iPad isn't keeping up anymore. The M1 Macs just shoved me in that direction a little faster than I thought they would.
No shame in returning the iPad if it's not for you. Like others have said, if you want it just for watching TV and listening to music, you might feel a little better about the base model. They're still very powerful and work great with the first gen Apple Pencil.