In Blade II, Scud is ordered by the bloodpack to hold open a reaper's mandibles while they're dissecting it. Scud is reluctant, but Blade calls him a "sissy" so he goes ahead with it. It seems out of character for Blade to back a bit of vampire bullying in favor of his human companion, but the end reveals that Blade knows that Scud is a double agent, so he doesn't really gives a damn about Scud.
In Blade: Trinity, Dracula/Drake has a One-Winged Angel form. One of the more noticable features of said form? His jaw splits open. It seems Damiskinos was closer than he thought to making a "perfect vampire".
In Blade, the zombie-like vampire and ex-boyfriend of Karen, Dr. Curtis Webb, is never killed in the final battle. He's still down there.
In Blade II, the gene splicing that turned Nomak from a regular vampire into a super-powered Reaper also leave him in constant, agonizing pain. Now consider the movie also stresses that because regular vampires can regenerate most damage, they have a much higher pain threshold than humans - to the point that vampires are seen kissing and masturbating with razors. So for Nomak, a vampire turned into a Reaper, to state that he is in unbearable agony, he must be experiencing an almost unimaginable level of pain.
Deacon Frost's plan is to summon the Blood God, which will turn all humans into vampires. Why would a vampire want to do that? It would be like a lion turning all its prey into lions. If everyone in the world is a vampire, who will the vampires feed on?
It was originally explained that he keeps refrigerated humans to feed on, but this was dropped for being too expensive. It was realised in Blade: Trinity.