RAAM has a Full Screen, projectile invulnerable, armored roady run Command grab that applies poison.
His Dominance grab also has multiple incarnations that are faster (and with better range in some cases) than a jab or throw. The stomps can lead to flipouts for entire life bars taken from grabs, and if your opponent is break happy they serve as easy counterbreaker bait.
Plus, his instinct forces the opponent to choose between repeated grabs or a massive one chance break cash out (or worse, if you lock out early and he gets to let it rock), while simultaneously making both harder to defend against.
If a Hisako is trying to grab you a ton, jump out of it. If they’re countering a ton, bait the counter with an empty jump or by stopping pressure for a second.
All versions of On Ryo Zan are unsafe on block, so her grounded mix-ups are easy to defend against once you figure out how to block them.
Both her dash and her teleport leave her wide open for a kick in the face.
Possession can be countered by walking backwards in some situations, and jumping in all situations.
If you’re getting caught trying to counter the suck, you’re probably getting eaten during start-up.
Look, General RAAM may have it kinda hard in a lot of areas, but where he excels he dominates. Hisako is more general with some more tricky options, but she also has a lot more to lose if she guesses wrong since whiffing her grabs/counters or overusing her dashes/teleports leaves her wide open to get clobbered in the face. I’ve played a lot of both Hisako and RAAM; got them both to 50 and have wielded them both to varying degrees of success against both friends and randoms. I can even tell you there are characters who’s grabs I’m much more afraid of than either Hisako or RAAMs, if only because I don’t run into nearly enough good RAAM players (even Hisako is kinda hard to find at times). Kan-Ra and Gargos have both at different points scared the hell out of me with their grab games.
It all comes down to preference, really. If you think Hisako’s game plan sounds like more fun, give her a whirl. If you want to stick it out with RAAM and learn to get better with him, let him continue his march. I can tell you from experience both characters have their own merits and rewards, as well as shortcomings.