We don't know why the Ovation Breadwinner was retired from backup duty. Perhaps the shape was simply too "out" even for a visually flashy band as KISS, perhaps it was deemed too expensive. The backup guitars that would define the early career of KISS weren't necessarily cheap guitars but a number of them were basic, slightly more entry-level models. Like this 1964 Gibson Melody Maker. The fact that it is a 1964 is simple deduction. The 1962 Melody Maker had a single cutaway Les Paul-style body and the 1963 had a more bulbous pickguard that extended into the area below the wraparound bridge. By 1966 the Melody Maker had gotten the "SG makeover" and gotten a completely different body. The Melody Maker is first seen on January 26, 1974, but it can also be seen in the In Concert footage if you keep your eyes peeled just as they go into the riff of Nothin' To Lose.
The Melody Maker had all the specifications that Ace (and Paul) appreciated. Mahogany body, a one-piece mahogany neck and a rosewood fingerboard. The downside was the TPBR wraparound bridge which, although it was compensated, didn't allow for fine-tuning intonation, and the PU380 pickup which was a single coil whose output couldn't compare to the humbuckers or even the P-90 in their other guitars. On the plus side was the low cost.
The Melody Maker had a 1964 list price of $127.50 which was a far cry from the $349 commanded by a 1972 or '73 Ovation Breadwinner. If bought used the difference in price would be even greater seeing how the Melody Maker was an entry-level guitar and ten years old. For a band with virtually no money it was a smart choice of backup. There are no photos of the Melody Maker actually being used but it shows up in a handful of photos over the first half of 1974, and when it does show up it's always standing on Ace's side of the stage side-by-side with Paul's Gibson Les Paul Custom '54 Reissue as seen above (and below). However, most places they played during this time were relatively small and there wasn't enough space on stage to have the backup guitars there, and the available photos are very few.
There is one minor twist to the story before the Melody Maker rides into the sunset. The Melody Maker that shows up on Ace's side of the stage in Detroit, Michigan, in mid-April seems to have a stop tailpiece, something the Melody Maker didn't have. (The photo from Long Beach further down has a better view of the stop tailpiece.) It could very well be that the lack of intonation adjustment became too much for Ace and that the bridge was changed. It could also be a different 1964 Melody Maker. Paul has mentioned more than once that they used to hock guitars to be able to afford food so it's not outside the realm of possibility that that fate could have befallen the Melody Maker seen in the In Concert footage and that this is a new aquisition.
The last known appearance is in Long Beach, California on May 31, 1974, as seen below. Judging by the guitars used later in the summer the Melody Maker was probably among the guitars that were stolen during the Hotter Than Hell recording sessions at Village Recorder in August.