I personally find Karin a LOT more fun to play than Cammy, but there is an appeal to Cammy.. Her buttons are just.. good. I think footsies with her can be interesting and fun - but I'm not a strong neutral player.. if I'm good at anything (debatable) it's usually reads/mindgames/offense.. But some of what make the neutral fun with Cammy is just how much she can dominate it. Set the dummy to block and chain st.lks into it and look at how little pushback that normal has. 4f, +1ob and excellent range for what it is. Every medium button she has is nice.. her heavy buttons are good.. Using her f.hk (the double knee) in neutral is 'bad' but you'd be surprised how well it works vs dash happy players.. its a lot of active frames to put out there (dont do this vs good players, they will beat you to death with your own knee caps, but its a thing and its funny when it works).
I feel like to do well with Cammy, like actually well, you do have to have solid fundamentals, and she's a good teacher of that kinda stuff. She's very strong and she can win so many neutral situations (this is good for learning for a lot of reasons) but shes very fragile and vs decent players, you cant miss confirms, you cant throw out bad DKs.. She does take fairly solid and clean play to win with, but shes powerful enough to make up for less than perfect play, and give you time and options to learn what you're doing.. without carrying you entirely.
As to your previous questions about Necalli and Karin.. For whatever it's worth I'll give my opinions. Just a heads up, these opinions are based on online ranked strength/viability. Not about how well they'd do in tournament/offline/evo/daigo/whatever strength. Of course, in the online/ranked environment any character can win and any character can climb the ranks. Some just do it more easily. An example would be Cammy. I dont think shes a strong ranked character, even though shes arguably the best character in the game - though I think shes a good character to learn with.
Necalli is strong IMO. He has 3f buttons. DPs. Decent normals. VT1 is a nice, easy to implement VT that you can almost always use in some way. He has fake shit, real shit, shit in the middle. He plays SFV well enough. Damage. His dash game is great, especially online, lol. I think, in ranked terms, he's very strong. He isnt super hard to win with and doesnt take complex or situational stuff to be effective.
Karin is strong too. Really good buttons. Great movement. DP. 3f. She's good at turning meter into more damage and shes easy to pressure with. She's harder to play well than some as you climb and play better and better players though. She's a nice mix of 'just do stuff' and fundamental play. In ranked terms I think shes good, but not amazing. Lagg/Less than perfect connections can make some of her stuff wonky and unreliable. She's not as forgiving as some characters. She requires proper meter management imo.
Tournament/offline viability? I dont see them as top tier, but both are strong.
