Actually, screw it, I will bring up Alucard.
Alucard the Vampire Power List:
Immortality
Invulnerability
Advanced Regeneration
Superhuman Senses
Superhuman Speed
Superhuman Strength
Intangibility
Defiance/Manipulation of Gravity
Shapeshifting
Teleportation
Telepathy
Hypnosis
Sharpshooting Skills
Summonning of Familiars
Creation of Fledgelings
Advanced Combat
Memory Absorption (Through Victims' Blood)
High Resistance to Most Vampire Weaknesses
Omnipresence (Spontaneously Appear and Disappear at Will)
I admit, Rika Furude is powerful, but I believe Alucard is more so.
Alucard himself is much tamer than Rika, and much more caring for the well-being of people, which means that he doesn't just let loose on his powers like Furude does. This is shown by the fact that the British Hellsing Organisation seals Alucard away for a period of at least 10 years, believing Alucard to be too powerful to use. And if you know anything about the British, you'd know that they don't lock up a weapon that'll give them an advantage in battle lightly. They really only do it if they could wipe out the entirety of the human race with it.
Alucard himself is a powerhouse. He has super strength, speed, and senses, meaning that he is stronger, faster, and quick in detecting the presence of his enemy and being able to react. Alucard himself is near immortal. The only thing that could ever kill Alucard is a human, meaning that this guy already has the advantage against most super-powered enemies he faces, as they are not human. Alucard also possess regeneration and invulnerability. If you've ever watched the Hellsing anime, you know that Father Anderson decapitates Alucard in one of the first episodes and proceeds to hunt down Seras, only to be stopped by non-other than Alucard, who was completely unscratched. The regeneration abilities that Alucard possesses pretty much mean that he can reform his body whenever he wants to. It won't take him 5 minutes or so to slowly reconstruct his legs unless he decides that he wants to screw around. In addition, Alucard can manipulate gravity. Doesn't really matter how powerful one is if their body is crushed under the weight of gravity.
BUT WAIT! THERE'S MORE! Alucard carries the ability to shapeshift and to teleport. Think you've got Alucard in his humanoid form? He'll just transform into something else and keep hacking away at your sorry ass. Or, if he's feeling playful, he'll teleport away and come back from a different direction. Or multiple directions. He has guns, after all. He can keep teleporting around and shooting you from all different directions, so you wouldn't know where he is. Not like you would in the first place. Alucard has the ability of Omnipresence, basically meaning that Alucard is everywhere, but nowhere, all at the same time. Think you can hit someone that's everywhere and nowhere at the same time? Okay, go for it. Come back and tell me how it goes.
Don't stop reading now. We're not done yet. Alucard also has the ability of telepathy and hypnosis. He can ram his own thoughts right into your bloody head. Think of how distracting that could be, if he's taunting you from your mind the ENTIRE FIGHT! If you could focus during that, I give you props for that. However, Alucard can also hypnotise people. So let's say he's feeling playful, he could always go and find your mother, hypnotise her, and then bring her back to the battlefield and have her attack you~ Oh, but how does he know my mother, you ask? Well, Alucard has the ability to absorb your memories by simply drinking your blood. Let him get close enough, and you're practically screwed. He can absorb all of your memories, and will keep them within his head no matter what happens~ That means he knows all your weaknesses, strengths, loved ones, basically everything about you. Ain't that swell?
In addition, Alucard has a high resistance to every natural weakness of a vampire. Think sunlight will kill him? Psh, good luck. Oh, you've got some garlic? Alucard eats that for breakfast. Set him on fire? He walked out of the burning wreckage of a German Zeppelin untouched. Silver bullets maybe? Tsk, ha! Good luck hitting him~
Now, of course Alucard cannot create and destroy entire universes at the pull of a trigger, but he is much better than Rika Furude in several regards.
What appears to be a main difference between them is that Alucard has respect and compassion for many people. Unlike Furude, who, from what you've presented, appears to fight for herself and herself alone, Alucard fights for a cause, and doesn't fight unnecessarily. He fights to defend the people of the United Kingdom, and his mistress, Integra Hellsing. He appears to try and avoid innocent casualties if possible, but will kill innocent people if it is for the greater good of his cause, seen in the first episode when he shoots Seras through the heart to kill a vampire who had been terrorizing Cheddar Village.
What more do you need than that?