Sergio L. was god.
Sergio C. could have become the negative god, but refused. At least he was god for 2 films in 68 and fell from grace soon thereafter.
The best behind them was without any doubt Guiseppe Collizi.
Never a genius, but a rather talented guy. And he seems perfect in hiding himself.
Then Sollima, even if as a director he probably wasn't as naturally gifted as the following ones (but tried hard to compensate it, and succeeded at least for his SWs):
They all had a certain western feeling, and some of them had always to struggle with minimal budgets.
Maybe the same category, but I'm not exactly sure, as I really disliked their films only a few years ago:
Parolini (for his Sartana,Sabata outings)
Carnimeo (I like his style meanwhile)
That's it, and only directors with at least 3 genre contributions.