First of all, they’re not just assassins they also include sorcerer and Viziers (scholars of a sort), all with their own specific powers. There’s something sad and desperate about having a vampire clan full of nothing but bad arse assassins, but damned if the Assamite don’t manage to be kind of awesome anyways. If you want to play a classic, awesome vampire, then Ventrue is definitely the clan to choose. If Dracula were a Vampire: The Masquerade character, he should have been a Ventrue. Ventrue have the best “normal” set of powers in the game, including Dominate and Presence, which makes them the charismatic vampires who can make their enemies piss their pants in fear or make them fall in love with them even as they drain their blood. The Ventrue are usually successful, rich, and in charge of vampire society called the Camarilia, which enforces the Masquerade, which is the social pact vampires have to keep their existence secret from mortals.
They’ve been a part of the Roman Empire, the British Empire, and pretty much all the empires in-between. As the most noble of vampires - at least they consider themselves to be - they infiltrate and use human government to maintain their power over other vampires. Ventrue represents vampires at their most classy.