What to do with this fire place?
Our house was built in the 1970s and we had a similar dilemma.  We covered the brick added a new mantle added black granite tiles as well as covering the opening with a cover we bought at a home improvement store.  We also widened the area a little as well to offset the mantel.  With the doors shut it looks very modern and clean and hides the internals.
Hopefully this gives you some ideas.
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