In some jurisdictions, you can meet the energy requirements with a performance model (rather than meeting the prescriptive values). For example, if you want your windows to have a higher VT (and therefore also a higher SHGC), you can install more efficient HVAC systems or insulation to counterbalance. We are in CA and often take this approach when windows don't meet the energy requirements.

I have low e windows and they have no real effect on light trnsmission

The glass is made by glass manufacturers and basically all the window mfrs purchase from the same core group. Yes there are different Low E coatings and yes they all do effect VLT. But your area of the country determines the glass type you need to use. And after the house is drawn, permitted and construction starts is not the time to determine the specifications for the window you want to use. And the windows will be required to be Low E, I do not believe you will be able to get around that with the newer codes. The better window companies offer different glass with different Low E coatings so if you would like more advise you need to offer more info.

In a cost vs. value scenario, spending 300K on windows for a project isn't going to give you 3x as much light as spending 100K.

i agree there is a substantial loss of light with the new windows. all of my openings are the same size. some are 6 year old pellas, some 35 year old aluminum combinations, and some 146 year old originals. with the pellas, its like the sun never comes all the way out, and you dont notice til you walk through another section of the house with the older glass (and blue sky!)

the pellas are not coated or tinted, just low e. sigh.

I got used to the slight change in light very quickly, doesn't bother me a bit. What the windows do though is alter interior colors, especially paint. That was a surprise. Neverthless, what a huge improvement here in Southern California. Comfort and energy efficiency coupled with vastly reduced electric bills make up for what I'm not thrilled with.

My new doors with the state mandated coating are hideous. The coating (which they say is invisible) gives everything a cold, dark feeling. I will be researching ways to remove it. If it is impossible, I'll go get some surplus doors, but they'll be far less efficient than the current ones would be without the coating.

Low e definitely darkens room and in summer makes you feel caustrophobic

We just had Low-e 3 windows installed because we didn't know Low-e 2 was an option for our area :( They are positively teal and the indoor light is greatly reduced. I was so excited about having new windows that would slide nicely and reduce noise and drafts and now I feel like our house was ruined. Maybe I would have felt the same way with Low-e 2, but I will never know.