how many marks was the question worth, and what was the source exactly: equestrian statue?
anyway, a few points you could have mentioned on:
- The Proconsul Marcus Nonius Balbus donated the Herculaneum Basilica, which is confirmed by statues of himself, his wife, daughters and mother.
- He also built the Suburban Baths, which is supported by statues and inscriptions.
- Funded games/spectacles - others did this, for example the Holconii family gave themselves a golden seat there so they would be visible and their contribution would be known. Just like those that put equestrian statues in the Pompeiian forum.
- Built statue of Vespasian - link between politics and the imperial cult and hence important to social cohesion, i.e. he was in the cult of Augustus, participation in a priesthood was part of a political career path. Another Augustale was Lucius Mammius Maximus, who donated the town markets (I think he may have also been related to the public priestess Mamia, but I'm not sure)
use that information about his spendning on the public as a jumping point to go into the Patronage system (more clients you had the better you were) and the expectation that wealthy officials would use their funds to entertain and build facilities for people.
there are plenty of inscriptions and graffiti to mention, even political satire, i.e. 'All those asleep and Macerius ask for Vatia as aedile'.