Regarding Hsien-ko:
I think she can actually be a solid character, but you need Clockwork-like execution to do it. I messed around with this concept for a while in training mode, and then took it to real matches, and I was very successful, but it's just too hard for me execution-wise (even without the bad netcode, I'm just not there), and if I wanted to really make this work, it would be a Dormammu-less team, which I simply do not do - I wish Dormammu had a meter building assist, it would fit him well:
Wesker (Samurai Edge)/Hsien-ko (Henkyo Ki)/Morrigan (Dark Harmonizer)
Your goal is to delay with Wesker at the start while calling Dark Harmonizer to build a few bars of meter. If you can land a combo, that's great, but it's not necessary. Hsien-ko uses Henkyo-ki because, as great as Senpu Bu is, it's also very risky, and she takes massive damage while doing it. Henkyo Ki, on the other hand, has very few active frames, and protects itself very well from projectiles. You will be using Dark Harmonizer most of the time anyway, and your goal is to dominate with Hsien-ko on point.
If you get a hit off, try to TAC Hsien-ko in to start the fun with her. If not, try to create a situation where the raw tag would be relatively safe. You want to get Hsien-ko in the game with ~3 bars of meter stored up. Once Hsien-ko is in, use Rimoukon, and start to pressure your opponent. Rimoukon's duration allows you to make ~3 Dark Harmonizer calls, which give you 90% of a bar of meter. You cannot build meter during Rimoukon, which means you will lose 10% of your net meter every time you Rimoukon if you go straight from one to the other.
One of your goals is to fix the gap in Rimoukons. The best way to do this is to ensure, as much as possible, that your opponent is in a blockstring, and your normals build a little meter from the blockstring. At the end of your blockstring, cancel your normal into Henkyo Ki, and then cancel Henkyo Ki into Rimoukon, and continue applying pressure.
Why Wesker? Samurai Edge allows two things:
1) Unblockables. Hsien-ko has a great air pressure game, because you can jump, air walk, and then immediately cancel into two j.Ms. Hsien-ko is one of the few characters that can stay in the air without entering flight mode, which allows you to properly time the Samurai Edge.
2) Relaunches. Hsien-ko does crap damage without hypers, and you won't have access to anything but Rimoukon unless you want to kill a character. Plus, since Rimoukon does not last long at all, when you do hit your opponent, you are almost guaranteed that Rimoukon will run out mid-combo. The ability to relaunch extends the period of time during which you do not need Rimoukon up, and thus also extends your meter gain from normals that hit your opponent.
Why Morrigan? Dark Harmonizer can be used more than Bloom. That's the primary reason. Other than that, Morrigan is a more solid anchor, and with this strategy, if you screw up, you are guaranteed to have a ton of meter to spend on Astral Vision. Morrigan also makes great use of Wesker's Samurai Edge. You don't even necessarily need to anchor with Morrigan; if you want, you can put Wesker in the back at some point if you are more comfortable with him.
Why this strategy?
1) Hsien-ko is actually a good character in this strategy. I have come to believe that Capcom balanced Hsien-ko around what she can do with Rimoukon. She is the only character in the game with an ability anything like this, and people seem content with using it to buff her assists only.
2) Your assist calls are always 100% safe with a hyper armored Hsien-ko. The concept of "punishing" you simply does not exist. Anything your opponent does, you simply walk through, and your opponent pays a much more severe price than you did in eating a little damage while walking through the attack.
3) Your opponent cannot call assists, for the simple reason that your opponent has no way to pressure Hsien-ko. Even if your opponent wants to call Tron or Haggar, this does not stop your onslaught.
4) Remember, Hsien-ko has command grabs. If you don't want to use Samurai Edge for unblockables, grab your opponent instead. I honestly do not remember if you can Samurai Edge to OTG from your grabs, command or not, but I would not be surprised.
5) It's fun and unique! No one has tried this, and it really works, and I'm not even good with Hsien-ko or execution. I think if someone took the time to master this setup, they would be surprised at how effective it can be.
Ending Comments:
Don't expect to destroy your opponent's entire team with just Hsien-ko. If your opponent is bold, he will make you take damage for every approach you make, and you just need to accept that as part of this strategy. You will generally need to clean up with Wesker and Morrigan. Every time you block, you place yourself in a position where your opponent can keep you in blockstun, which means you are losing Rimoukon as well as Dark Harmonizer time. Sure, you probably want to block a Shinkuu Hadoken, but not something like Sentinel Force. I am not sure if this is actually viable at high level competitive play, because it does have its problems still, but for those who love Hsien-ko, and wish she were worth more than Rimoukon followed by Senpu Bu assist spam, I recommend you give this a try. If you feel so inclined, you can always replace Wesker with any other character that has an OTG assist, or use Amaterasu in place of Morrigan.