I never really bothered with Helena before DOA4, but once DOA4 was released, she quickly became one of my mains. When I then went back to DOA3 and DOA2 Ultimate, I found that I just couldn't play her in the same way and didn't enjoy the experience at all. It's amazing how some characters can lose or gain so much between iterations. I had a very similar feeling with Tina - a bit poo in DOA2, awesome in DOA3 and back to being a bit poo again in DOA4 (although it looks like she's going to be pretty formidable in DOA5).
Its weird how in the past, we basically had to shut up and put up with whatever we were given in new DOA games, but we've had a crazy amount of opportunity for input with DOA5. I guess we should be grateful for everything that has been noted by the community and addressed so far. Hopefully the concerns with Helena will also be addressed. We know that TN are aware of the situation, so I guess now we just have to trust that they'll take it on board.
Its a shame that the other characters haven't been as passionately analysed as Helena though. I hope that doesn't lead to a lesser experience with them. Helena is clearly very popular...hopefully that will pay off for her fans.