Most players online play casually - but I have seen a number of players that I've come across worth noticing. Does not seem like they are involved in this site.
In regards to players that I have seen, although very online heavy, I've seen Galacticallstar do some very interesting things with Ayane that I've not seen many others do. xxSnipexx2 (I think) is also very impressive. I saw His_Reverence play and he was quite impressive with her. JagermeisterS2 also tried his hand at Ayane.
In terms of Kasumis, Kwiggles has a great Kasumi now. X-BlurredVisions is also talented with her. I ArtemisX I plays many characters but is still very solid with both Ayane and Kasumi.
I was thinking of learning them. I am currently playing Nyotengu and Brad.
Arion & Gill Hustle are pretty solid. G-Allstar, Rev, & Snipe are decent enough but they haven't really proven themselves outside of an online environment and lean a bit on the online heavy side. I'm not sure who JagermeisterS2 is. Is that Jaegar?
Kwiggles is fantastic with Kasumi and Blurred Visions is ok. Artemis is pretty decent.
A lot of players online (that only play online) actually play the same way, regardless of the characters they play. I've played and done so many different experiments from practicing online to know that most players online don't play with strategy.
You can say those list are subjective but they are actually quite accurate, speaking more of Force's list of Ayane players. Most of other players who play the character "who you think are good" actually play the same way.
Infact the only real difference in any of them is who strives for a Critical Burst more than the other. Other than that, most really only utilize the same thing to get damage in the exact same way.