A lot to unpack here, but let's try.
Before I start, I will point out that I'm building a home intended to be pretty blasted efficient, and I did a crapton of research before building it - and did so before I became a building official.
Then it is not healthy to live in so we add in replacement air and an HRV. That needs a drain so the plumber got to be paid for that. The drain might dry out so now need a little pump to put water back in the drain. That will break soon and most people do not even know they have one or what an HRV is or even if it is running or not.
The common approach is to run a small hose to a drain. Proper planning will ensure the p-trap is suitably charged. Often/usually, the HRV hose is looped to create a trap as well. In my house, I ran the HRV hose to the washing machine platform, which is designed to handle failures of both the washing machine and hot water tank. The p-trap for this assembly is charged by the washing machine. Won't dry out unless I don't do laundry for a few months.
The situation you describe above is the result of poor planning, nothing else.
Now we have this condensation problem so have to have a whole house dehumidifier or other equipment as described above.
Properly ventilated houses will not have condensation problems.
I am still troubled by this declaration you have concrete in contact with earth. When I questioned if it was properly insulated, you said 3" of foam. Either it is insulated, or it isn't. If it isn't, then that's a big part of the problem.
That means at times it will be too hot. So now i need a cooling system of some sort as well which most people in Maine do not have because the season is short.
You have a concrete slab. That should act as a thermal flywheel and keep things cool. I have 5" of concrete on 4" XPS as a slab. When the workers were heating the place last year, the house was comfortable for several days after the fire went out, without extra energy inputs. Likewise, in summer, when it's scorching hot outside, the house is several degrees cooler. That's an established principle in efficient house construction, and manages to keep the house cool in summer without any energy inputs.
It sounds to me like you might have too many south-facing windows that are exposed to full sun. Again, proper design approaches will eliminate these issues: in my house, I have two massive 4x7 goth-arch windows, but they are under a 3' soffit overhang that screens direct sun from the peak summer months.
Again, don't blame efficiency for what bad design has caused. The general principle for passivhaus construction is to have window area that is no more than 10 per cent of the floor area, largely because windows are woefully inefficient. It's also worth noting that fewer windows = less window condensation.
Most people means most people in Maine who do not make a lot of money. It appears that on the alter of energy savings we have created homes that are a lot more technical to build and less affordable for most people.
The above sentence speaks to the shortsightedness that many people have. "I can't afford to build an energy efficient home, but I can't afford to heat and cool a home that isn't energy efficient!"
In beaurocratspeak, many fail to balance capital costs with operating costs. When I volunteered for Habitat for Humanity, which aims to pair modest-income rent-trapped families with affordable homes, energy efficiency was always calculated into the equation. Without going into a bunch of details that I can't remember after 15-plus-years, the proven approach was to spend more up front to reap long-term savings.
I will use an HRV as an example. When I did the research a couple of years ago, the cheapest suitable HRV for my place was $1000. It drew 144 watts per hour. That means its annual cost for electrical service was (3.45 kw/day* 14c/kw=48 cents/day=$176/year. I purchased a unit whose power draw is 18 watts/hour, but it cost $2,000. (.43 kw/day * 14c/kw=6 cents/day=$22/year.) After six and a half years, the "more expensive" HRV has paid for itself.
The best cost/benefit expenditure in home building is insulation. I don't have to explain that to this audience.
Perhaps we went a little to far with energy savings at all costs. The result is that about half the population cannot afford these kinds of houses.
I live north of Maine. I see homes that are tiny little things, or old-style trailers because people are broke. They're often well less than 1,000 square feet, and often heated with wood. Cords and cords and cords of wood.
Here's the capital/operating cost argument:
Based on conversations, the occupants of a 16x60 trailer go through five to six cords of wood a year. The average price for a cord of hardwood is $325-plus. That means, say, $1,787 in heating costs per winter.
I've spent multiple winters in a well-insulated 500 square-foot cabin (R40 ceilings, R22 walls R26 floors). Wood heat as the only heat source. I've only ever exceeded one cord of wood ONE winter.
The cost of upgrading a trailer's R12 walls to R17 (40 sheets of XPS foam at $30.20) =$1,208 plus tax. Hell, throw in some added vinyl siding and bits for $500. Based on crude calculations/extrapolations, going from R12 to R17 walls will about halve the heating costs in the typical trailer, or in other words (~2000+893*2=$3785; 2x1625=3575) the insulation upgrade will almost pay for itself in two winters, and thereafter be LESS costly.
The same metric applies to all structures. Energy efficiency very often pays for itself in reduced operating costs. Time after time, you will find that in most cases, a cost-benefit analysis will show it is better to have a higher capital cost to invest in energy efficiency, which will recoup that extra investment through the reward of a lower operating cost.
Or, in other words, NOT going to energy efficiency means about "half the population cannot afford" energy inefficient homes.
I am going to go political here: one of the greatest opponents to energy efficiency are the American energy companies who stand to lose a lot of money if people invest - that's a very intentional word - in energy efficiency.