I would say Victor's motives may not have been motivated by evil, but rather shock and fear. He ran away from his creature because it did not resemble what he thought it would. The Creature's actions, by comparison, are much worse than simply leaving someone, yet in most of them he is driven by anger. Since Frankenstein created the monster, it could be argued that his arrogance brought his troubles down upon him, thus starting the whole chain of events.
The case can be made that Victor Frankenstein is indeed more evil than the creature. The creature takes the path toward evil as a result of the evil he has experienced at the hands of others, specifically Victor. In a sense he is "justified," being treated as evil before actually being evil. He was created with a desire for acceptance. When this acceptance turned to rejection at every encounter, he was labelled "evil," and thus became what he is assumed to be.
Victor, on the other hand, came from a loving family, with an environment of acceptance and support. His choice of evil (in hating his creation) was not justified by his upbringing. Evil was a conscious choice on his part.
Whether or not there are gradations of evil, it is still telling when evil is a personal choice, with no one to blame but oneself. The creature's evil was more particularly revenge. Victor's evil was putting himself in the place of God and the rejecting his creation.
I think the previous' posts have done a very good job of articulating the complexity of this topic. I am in real conscious agreement with post #4. Victor is completely to blame on this one. His abandonment, (out of shock, out of fear, or even out of self serving elements) of the monster is rather brutal. "Evil" is a tough sell, but I will buy it because I think abandonment of any creation is painful. It would be one thing if the abandonment is done with some stipulation for the creation's health and understanding (Leaving children at orphanages, adoption, etc.) This is not the same as what Victor did, which is running away. A man of supposed princples and "science," should have exercised the moral and ethical responsibility to stand by and with his creation. I think Shelley might be making a statement on the nature of science and how the consequences must be acknowledged. Victor's abandonment of the monster shows a great deal of cruelty, unintentional or not. I sympathize with his shock at creating something that was not intended in terms of form/ physique, but the reality is the creator has to bear some responsibility and ethical standards have to be upheld for loyalty to it. I know I might be coming down a bit harsh on Victor, but I think there was something poignantly sad when the monster comes to the realization that he is a "wretched creature" who will never face or experience the voice and feel of love and companionship.
I don't think so. Frankenstein chooses to abandon his creation. It is no different than giving birth to a child and leaving it out in the streets to the mercy of the elements and wild animals. He knew what he was doing, and he chose this route. In fact, you can trace it all the way back to the beginning of his experiments--he continued to write in his journal that he found his creature "beautiful" only to discover how wrong he was when the creature took his first breath. We have all made the mistake of not thinking through to consider the consequences of our actions. However, instead of running away from the problem, thus creating more problems, the mature thing to do is to deal with the issue in the best manner. Victor did not do this. He brought it all on himself. With a little love and acceptance, the creature would have been nothing but a pussy cat addition to the family. Victor is to blame for his vanity and selfish nature, and he paid the ultimate price.
I suggested an answer for a similar question earlier today. You might want to read it: http://www.enotes.com/frankenstein/group/discuss/frankestein-50615
I believe they both in the end lose their humanity and sanity. However, as soon as Victor had created the monster, he left it on its own and it was forced to traverse the lands alone and learn like a newborn baby. This creature starts to become evil once it is spurned by society and sees no other way to receive their love and because of this turns into the monster he is.