If it were mine I would be making the rounds of the dollar stores to get hydrogen peroxide and getting the FC down. Once the FC is below 10 ppm which will be a sort of pale amber yellow on your OTO test kit. You can retest the pH and adjust from there.
I just use liquid chlorine (I have an injection pump to semi-automate additions and tweak things by hand), and for CC build up I occasionally use MPS, but find that is only needed after a large pool party. I did invest in a UV ozonator a few years back shortly after I started using the TFP method, however I have never felt the need to install it. (maybe one day I will, just as a belt and suspenders sort of approach, but I doubt it). Having said that my pool is often under utilized with fairly low bather load, if you have lots of kids in the pool all day everyday either a UV or Ozone system may have benefits. My suggestion is to wait and see if you have a CC problem before looking for a cure. As to humidity, when my pool was built 35 years ago it originally had a central air conditioner system, this had all sorts of issue (from cost of operation to condensation dripping from the vents), so when the roof was replaced a couple of years ago I installed a pair of high volume exhaust fans which you can see in this thread
My not indoor pool at the moment They are sized to be able to vent the entire air volume of the building in about 6 or 8 minutes, so we can leave things shut up and warm in the spring / fall, yet suck all the humid air out quickly. This lets us get fresh cooler air inside, but not loosing much heat from the building.
p.s. there is a little bit of learning curve on the TF-100 although most master it quickly and there are you tube videos to walk you through it, also if you order it consider getting the speed stir accessory, no one regrets it.
https://www.youtube.com/playlist?list=PLE98E18E2EE701C4D
also
SpeedStir Magnetic Stirrer - YouTube
(think of the speed stir as like an automatic transmission on a car, you don't have to have it, but it can often make life a lot easier) Perhaps not the best analogy since both my car and my truck have manual transmissions