I did a mystery quilt two years ago that my poor fabric choices meant the feature blocks didn't show the piecing well at all. I had too little contrast between my background (black) and print (black and multi-coloured). The print had too much black space and thus you didn't see the piecing/final design (think Maple Leaf block).
I intend to rip out all those blocks and replace with a single block of the print.
Lesson learned - I don't like mystery quilts where you don't know how the fabrics will come together. I've felt like this for awhile, but this one was the reinforcement of why I don't like mystery quilts.
It sat forlornly on the shelf because I didn't want to finish it like it was and didn't know how to correct it. I even tried decorative stitching around the design of the block to try and emphasize it to no avail....now it has a date with Jack the Ripper....

Sometimes in the course of a project we learn all we can or do all we want... I believe in consistency so try to do all of one stage of a process at a time, since I mostly make bed sized quilts that can be a lot of seams. When I was making my storm at sea a number of years ago, I put on all of the skinny triangles to the big diamonds the wrong way. Picked it all out and did it all again -- including putting them on wrong a second time! LOL I keep reminding myself as I correct things that the other option is to not make the mistake in the first place so learn by how much I hate taking things apart to do it the right way next time.

But sadly, my vision issues are making it harder and harder to see seams. It is not worth my time at this point to take apart an existing project. It might, however, be a very good time to start over!

Keep in mind that most masterpieces are not made the first time... painters may make multiple copies of a painting until they get just the right one. Photographers take thousands of off shots just to get the one good shot.

I would say donate it. Someone with a vision maybe able to do something with it. That might include cutting it up or quilting that plays up to the strengths or in other ways. But my advice is you learned that you want more contrast and life is short so move on to a fresh start :)

Oh, Keep it! If it is your first one, you can tell yourself if you are getting better on the second one. There is nothing wrong with doing this. I kept my first one and then knew that the second one was much better. That is how you can know you are getting good.

Mysher, I know the block by other names but is this the Scrappy Duo by Fons and Porter? I did a little searching and looking.

I was thinking that maybe if you haven't put the blocks together yet you could add another border around the blocks to add more contrast or to fade out the background a bit more. Either another mitered edge or a standard lattice. Obviously you will add to the size so figure out how many blocks you have to mess with first.

Otherwise, if you really want to fix the project, taking off just the background triangles from the blocks and replacing them wouldn't be so bad. Sometimes a little portable project while you are watching tv or waiting is actually sort of pleasant.