You just have to get used to how federation works. Their is bugginess from the influx of new users right now but give it time. A good way to get used to how federation works is using Mastadon (which also integrates with Lemmy on many instances)

I chose a small instance from the start and haven't gotten that much lag at all. The one thing that does annoy me is the refreshing on the mainpage (and then suddenly an entire communities' posts are all on top), but pressing refresh fixes that for me. Confusing? At first, but I don't consider myself knowledgeable about tech and I was able to get it up, running and personalised before even reading a single guide. I curently sort by "all" and "new", and just keep adding to my subscriptions.

Is there room for improvement? Absolutely. But I wouldn't call lemmy unusable at all. I actually spend a lot more time on here than at the aforementioned place. And one absolutely major bonus point: we can integrate images in our reply here. And I can copy/paste in the reply without it suddenly completely bugging out and not being able to type at all. It just works as its' supposed to.

Yeah, I hear you. I've tried a few different Lemmy instances and they've all varied in terms of bugs, posts getting stuck on the main page for days, not being able to load a post I made myself even though I keep getting comments on it. I get it, this is all new. But switching over to kbin made a huge difference. kbin.social is still getting killed from the amount of new users, but imo it looks and works way better than Lemmy while still being able to communicate with people on Lemmy. I'm not sure which system is newer, Lemmy or kbin, but kbin feels way more polished and responsive.