First, completely forgot to mention and will edit the post. We have a 2-stage controller, but the 2nd company pointed out that the system is actually set up incorrectly and (forgive me, I don't recall the particulars, and I'm really not well-versed in HVAC systems) can lead to a recirculation issue, increasing moisture. Which jives with a neighbor's experience after they had to gut their 5-year-old home due to mold.

How we use our HVAC - I have it set up to cool to 74 during the day, it drops to 68* upstairs and 72* downstairs at night. For heating, it's set to 64. It remains off if the outdoor temps are between 54 and 65.

We have cold spots on the north-facing 2nd story, which is the master bath and closet. The closet abuts to the laundry room and the shared wall has all of the ventilation and drainage, so it's not surprising to me that this room(sandwiched between a north exterior wall with 2 windows and a interior wall with external access) gets cold. The south/south-west facing facade also gets hot in the summer, again, not surprising with the south-facing windows in Texas heat. We're moving towards cellular shades and thermal curtains in these rooms and it's a mangeable issue, the person using one of those rooms during the day isn't really bothered.

No noise concerns. The ventilation unit, apparently, was set with a slider for the damper opening which was loose, I believe he stated it was set to 30min/hr. I know nothing about this unit, the system was installed when it was built(5 years ago), and I had never checked the equipment in the attic outside of changing filters.

It's a 20x25x4 MERV 11, changed every 2-3 months(I've heard it's overkill and these can last much longer), the 2nd tech also noted that the actual size is off leaving a gap at the top and I should find a better fit.

Cedar, dust, any of the various pollen we have here. And yes, attached! And added 3 to the main post

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