Titus must have learned something, he was one of the later Roman emperors. His younger brother not so good.
Titus was the second of the Flavian dynasty (the third being, as you said, his brother Domitian), but that was only the second dynasty, following the Julio-Claudian dynasty. He had the longest reign of any since Tiberius, and as long as his father and brother put together.
Since his assassins were the Praetorians -- officially the imperial bodyguard -- in conspiracy with various court officials, he was probably killed by corrupt a-holes who were about to be found out, as happened in the 3rd c with Aurelian (if I had to pick one, he'd be my favorite).
Subsequently Domitian was condemned, but it is probable that whatever reign of terror had been going on was due to corruption among the conspirators and the Guard, and got even worse under Nerva -- blaming the dead victim of the dangerous Guard no doubt seemed the safest course of action.
The Flavians rebuilt a chunk of Rome, erecting the current Pantheon (the original had been built mostly of wood by Marcus Agrippa) and the Colosseum.
What I get for spending too much time in between naps... I was talking about Domitian in the second half of the first sentence, the part about the length of his reign.