trying to bring down to dust the first man in Rome.
Looks like the family's favorite sport! :)

Quite agree with you that Scipio's special commission really set a big and potentially dangerous precedent (especially if we think how much Pompey benefitted from special commissions, and not all given in entirely transparent ways).
And... small-minded and petty jealousies of a clique of senators - as you call them - might very much be the real reason why the Republic went down. And change can hardly happen within the system, if those who are the system do not accept change.