the # one thing I want for rachel, really, I want ragna or jin's 5A. But meh, my advice
block low, watch for throws, you know the usual, but I just watch for her flip-over overhead attack and 2C it. The other overhead is a lot slower, but safter, FD it and you're out of pressure. But once you take away the flip overhead, a lot of tao's i've seen will just go all low's, throws, if you're smart about it, you can start doing j.2C3D out of their pressure strings seeing as how it hops lows, and beats throws.
Beyond that though, I've had chair beaten by more of tao's moves than any other character, I don't advise just throwing it out randomly in pressure. That's just gonna get you punished more often than not.
if she's in the air 6A, I don't really mind doing this randomly sometimes as its usually safe if they're in the air or i'll get a lucky counter hit. If she's on the ground, i block, if she's far away I'll use A ver. lobelia as it beats her dash, and low to the ground air dashes. I'll play really conservatively for this match-up until I know they're afraid of the counterhit. Once you get a pumpkin out, feel free to be really lenient with the wind, I'll blow 3-4 wind all at once just to tap this character seeing as it usually leads to frog combo. But generally tao seems to control the skies.
On the reverse, seeing as how she's so damn good at movement, I've also spent 3-4 bars of wind just to get away. Tech - air dash 6D, 2D to the ground, then 4/7D to push away the tao that's chasing after my ass, then I can finally get a lobelia or a pumpkin out
gotta run, might add more later