Seems to me people are too quick to dismiss a card as rubbish just because they've had little success with it, without considering how other people have had more success with it than their own preference.
Whether a card is good depends mostly on how well people use it. If SWAT Kat finds Cutey useful for example, that means it's one which they find useful and others don't.
Edwin will see some use, though not as much as he used to as Oshitsune fills the power-reduction niche better.
If Z4KALW3 is unsure which is better, nothing anyone can say will be anything more than a reflection of their own battles, which will probably have very different results to on their views to others views of the best card as people have their own unique playing styles
The best thing I think anyone could suggest is experimenting to find your own preference, try Pan in your deck for a few battles, Edwin for a few battles, and use whichever suits you more. For me it would be Pan, but if you find Edwin more useful, don't let anyone convince you otherwise as they are speaking in reference to their own style, which probably differs from yours.
If I had to choose one I'd lean towards Pan, but I've generally used them together. It's a preference decision that I'd make based on the the rest of the deck. It's hard to specify which is 'better' as they're good for different purposes.
The whole play-style point is true to an extent... if someone does well with a particular card, they'll be more inclined to use it over one which they've had little success.
HOWEVER (!) it's important to stay objective when building your deck, as well as when playing the match. Pick the card that complements the rest of the deck, and play according to what the situation asks for.
Going by the original poster's ELO record (yes I know that's not the only indicator of a good player) he/she is not a chump. Just experiment with the two cards and see which one feels like it works better with the deck. The verdict will vary with different builds.
Players seem to underestimate Edwin"s 5 damage and try to out pill you if played first round. This was a useful strategy for me when I was playing with the Nightmare.
Pan is a great card and he is a staple in my Nightmare but when I think on it a bit I may choose Edwin over Pan next time around if I needed to make a choice.
I would use both anyhow.
I have tried using Cutey but she does not cut it for me. Most people will easily out pill you with high damage card which makes her hard to use as a bluff or mid to late round card. I have not tried Timmy much but I am sure with a good stall deck he can be useful.