I'm cheap, so I only use cheap nibs from various sources online. The most expensive nib I use are the 3 for $20 flex #6 nibs from FPR. They work great most times, every now and then they need a little tuning to work just right.
It appears in your collection as if it is working for you and your collection is beautiful. Frugal. I like frugal better than cheap. After all, this passion does not allow too much for that word to be used with all seriousness. I am thinking in my own journey when I fell in love with Noodler's Ahabs. they are inexpensive, in fact believe the passion I had for Goulet nibs elevated the pen, since the versions I have only cost $20.00 themselves and the nibs cost $17.00 plush shipping charges. I feel much better having reused a couple of them on more expensive pens. You can't feel much regret about replacing a 14kt gold nib for a steel one. I learned that I enjoy the steel ones better than gold. Now, when I see a pen at some point of interest, I don't have to feel dissuaded because it comes or its nib can be replaced with a steel nib. Progress.