Intelligent Alpha I will try to answer you, you are making many questions and I'm not sure to have understood everything:
Wasn't she in an earlier game before DoaD? I kept reading that after DOA2 (3?) after she was defeated, she comes back again as Alpha-152. This is what boggles me. You mean, that Alpha should be discarded? I saw/see it like this:
Kasumi--->KA --->Alpha 152 ---> Phase 4 (who is wait ... Kasumi Alpha with a slightly longer name; yet, she didn't come back as Alpha-152?) So, it's this then (especially since the demise of clone #2 - KA ---> Phase 4)
Then, if you are talking of the story of the DoA series, we have actually 2 canon slighty different between them.
The first canon is the original one that follow the series from DoA1 to DoA4 where in this plot Kasumi Alpha is one of the clones created from Kasumi (apparently the better developed). Even if mentioned more times in the manual, KA appear only in a single cutscene in DoA2 where you fight her as Kasumi (the second enocunter of her story mode). After it you never see her or people talking about the clone, so it's easy to assume that she was easily killed from the original kunoichi and stop (definitely one of the worst use for a key plot of a story XD). Alpha-152 in DoA4 it's supposed to be a being that has nothing to do with Kasumi Alpha, just another clone that was mutated from DOATEC in a super being as according to their project.
DOAD anyway made a recalling of the first four games retconning parts of them (overall about the bosses' role) and now it has to be considered the new canon and the official past to the events of DoA5. In DOAD Kasumi Alpha has the same background of the original DoA2, however the character is finally characterizated and get the proper development of a key character, ending to appear behind most of the events. Finally even her fate appear changed, where her fate is to be mutated in Alpha-152 as last phase of the work on her (so the two characters in the new canon are now an unique entity).
Now about Phase 4, she is a character that has nothing to do with Kasumi Alpha or Alpha-152, she is a different clone that is part of a newest generation of clones, her powers and personality are completely different from the childish of the original Kasumi Alpha.
However, just like KA, Phase-4 share many moves with Kasumi and even ended to get the classic red and black outfit of KA. For this reason, knowing how people were asking for a return of KA in DoA5 even as a special skin, I think that the inclusion of Phase 4 wanted be a sort of answer of TN to the people wishing for it (exactly as Nyotengu for who was asking back Bankotsubo). For this reason I talk of Phase 4 as "spiritual successor" of Kasumi Alpha.
I hope to have answered to what you were asking.
My other question is, was KA (and Alpha was in DoaD as well) as messed up as Alpha was in 4? I ask since everyone knows how to play Phase 4 now (and it was stupid to have a "non-ready 'boss'" character). I know this doesn't necessarily equate to easy to beat, but if folks found a cheap loop to beat Alpha in 4, who's to say they won't do this if she's in 6 (provided TN handles her much better; however, we all know how Alpha was such a bitch ...)
I can't answer you, you have to ask this to the Kasumi players along the series or to the players of KA in DOAD.
By the way I heavily think that KA wasn't messed because in DOAD she got basically the moveset of Kasumi from DoA2U (where Kasumi instead inherited her newest one at the time, the moveset coming from Doa4). From what I know Kasumi was a very well balanced character in DoA2U (but in general DoA2U should be very balanced), but of course this doesn't say anything of concrete on the situation of KA in DOAD.
i think a total of one person cares about Kelly. guy is so obscure even Kronin didn't care about adding him
I'm not sure if this want be a compliment or less XD
By the way my point is just that I can't realize how people can care so much of a character that is never been realized in the series. I can understand something as "I like his design, I would like to see it used in future", but how to want exactly this character when you don't know neither what this means?