For what it's worth, I don't believe spoke quality, or even gauge, is the critical factor. Certainly not if you're under 200 lbs. The issue is spoke tension. And there, it's not even that important to have spoke tension uniform. As long as your spokes have sufficient tension, your wheel will hold up.
If a spoke comes in and out of tension under your weight as the wheel turns, it will fatigue and eventually break. In most situations, if one spoke is getting fatigued, they are all getting fatigued. So what you have to do is replace them all, and tension them properly this time. This much is necessary. More is not necessary.
You can replace all the spokes yourself; or you can have someone else do it. The former is cheaper; the latter is faster.
Better spokes? Butted spokes? Professional build? Whole new wheel? Sure! All of these are fine options. I'm not opposed to them; there is nothing wrong with any of them. They are just not necessary.
Bolded to emphasize that more replacing of single spokes and retruing is not going to solve the problem. All the spokes on there need replacing, whether the rim and hub get replaced as well is up to you.
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Bikes: 1996 Eddy Merckx Titanium EX, 1989/90 Colnago Super(issimo?) Piu(?), 1990 Concorde Aquila(hit by car while riding), others in build queue "when I get the time"