The main thing I've been struggling to find in a threadiverse app is a browsing experience like Apollo for Reddit back in the day.
I could see 1 post at a time, with the content fitted to fill the screen. If I scrolled down, it would load comments. I could swipe to move on to the next item. I found this flow to be very comfortable.
All the threadiverse apps seem to center on the big list where I scroll down forever. I can tap into a post, but can't just swipe to the next one from there.
All I've done to my Prusa MK4 is change the part cooling shroud. Great out of the box. Been bringing on it over a year. Works great right away even after sitting for a month.
IMO, of you felt interested enough to go through 3 cheap printers, you ought to get a decent one. That feels like justification enough to me.