utcminusfour
Lightwind upwind pointing can be a challenge! The Horue Tiny 120 is a relatively narrow board (isn't it around 78cm?)
for your weight and 7.5 that's on the narrow side and you may not be getting enough leverage over the foil?
Here is a couple of tips I found that helped..
1. Shorten the harness lines - I went from 31" to 27.5"
2. Raise your boom up
3. Depending on the draft of your sail, try moving the harness lines back a little a time.
4. I move the mast back forward 1" for my 7.8 and back for 6.7 and smaller.
its ok to unhook in super light winds and use rig pressure to drive upwind.
Last year, I found that I was twisting my lower back to drive through the foil and it was getting really uncomfortable (I weigh 205 lbs)
so by raising the boom and adjusting harness lines it made a huge difference.
In the pics you can see the harness line position difference between early summer 2018 (Green 7.7 V8 sail) and Jan 2019 (Pink 7.8 NP flight)
I am now loading up my back leg for more foil pressure, leaning out more and bit more relaxed grip (granted the NP flight sail is foil specific and very powerful sail). I foil the JP 135 in light winds 215 x 86