TPS One is also sold in a kit that includes their Signal and Canopy Boost products. Signal is made up mostly of K, Mg, and S and is used during flower. Canopy Boost is based on Magnesium Fulvate and is a foliar spray to be used in veg. They also recommend a source of Si, like their Silica Gold. Use of those products would definitely help with Mg & S.
I’m not totally sold on TPS One (or many single bottle nutes) because they have to make choices to ensure improper chemical compounds won’t form in the bottle that will cause issues for the plant.
That’s why I started using their Component Kit, which contains:
Part A
Part B
Silica Gold
CalMag OAC
N-Primer
Canopy Boost
Root Boost
Bloom
Signal
Link to labels: https://cdn.shopify.com/s/files/1/0549/4669/3369/files/Component_Kit_Labels.pdf
It’s a bit more fiddly when mixing, but it’s also a bit more customizable if needing to boost/lower particular nutrients.