I like the idea of a triumvirate, three people with a shared vision but perhaps with unique skills [0]. Hopefully all sharing a benevolent tendency to avoid things going pear-shaped [1].
You could say the same thing about dictators. The problem is not the power structure, but whether they are meant to be benevolent or not.
You could also say that a triumvirate is better than a dictatorship since there would be a small system of checks in place (not saying that Guido was being pushy with his position of BDFL, but it would be nice to see other ideas having as much ground as one person's ideas).
Sulla and Marius had pretty well smashed the republic a generation before. Not that Rome was ever really the idealized representation of a Republic that everyone at all points in time considered it had become debauched from.