Thanks for the idea, but this will not be coming back.
We originally had a full set of marketplace forums as you can find on
the internet archive. After the GE was released, these forums were gradually reduced to fewer categories until we only had 1 forum left called "Goods & Services". This forum was barely used at all, and when it was, the items were usually sold/bought by the person on the GE before contact could be made. Or we'd get posts like "go use the GE".
It was a pointless forum after the GE was released, there would only be 1 topic created on average per week.
Here is the last screenshot of what the Goods and Services forum looked like before it was killed off about this time last year:

If there is something you can not sell on the GE, chances are it is either junk and no one will buy it from you anyways, or you are dealing with rare items that are valued at much higher than the GE value. In that case, you would be able to find a successful trade much easier on the official runescape forums.