According to Roman sources bordering between folklore and history, Caesar was directly or indirectly warned several times that there was a plot to assassinate him. IOTL, he ignored these rumors, to fatal consequence. What might have happened had he rather either 1) declared the Ides an inauspicious day in his capacity as Pontifex Maximus, 2) done as several in his inner circle suggested and stayed close to Antony and other loyal and physically capable supporters of him in the Senate, or 3) somehow called out the conspirators in such a way as to destroy their plausible deniability--i.e. by exposing that each had borne weapons to the Curia on the Ides? Would he once again extend clementia to his opponents, or exile or execute the plotters?
What would be the lasting impacts on Rome as a whole? How might Caesar's reforms differ from Octavian Augustus' IOTL? Would Egypt/Cleopatra/Caesarion ever play a role in Roman politics, or would Caesar be wise enough to distance himself from Egypt?
Might Caesar retire after his reforms and allow some semblance of normalcy to return, i.e. becoming a Sulla Popularis? Would he die a natural death without relinquishing dictatorial office? Or would he be killed by a later plot? In either of the last two cases, would Octavian still be named his heir, or would he try to set up Antony or someone else as his successor?
What would be the longer-term impacts, and would the Republic survive in more than just name?