I thought 1900 searches on an exact term with low competition was a good thing, or at least decent? I am developing it as of right now and I am interested in the subject and can rank decently with content.
My question is why did a domain appraising site offer me $75 for just the domain if they can't sell it for more?
No appraisal made by a site is 100% reliable, they generally base the appraisal according to traffic and keyword. Domains are unpredictable assets and you do not know when a "hopeless" domain ends selling four figures.
I was planning on ranking it for various Christian music search terms and selling music through Amazon as an affiliate. I was also wondering how much I could maybe get out of it if I developed it in that way?
It is a good idea you can develop a showcase place for artists on this niche genre and perhaps some profiles of them and use affiliate links to similar music to Amazon. Regarding how much you will earn, that is unpredictable too but since the genre is a niche with no so many followers doing money in the mid xxx would be a totally success.