I agree off season is subsidising peak season but don't think it should, do you think someone getting the park 9-12, fireworks, F!, 2 parades, full rides (no reduced capacity/no non emergency closures) should pay the same as someone getting 10-8, no fireworks/F!, 1 parade, more ride closures/reduced capacity-personally I just don't think they should flucuate their offering so much and charge the same rather than treating off season visitors as less important than peak. I have no issue with Indy being refurbed these things need to happen BUT I think they should be waiting until after SM reopens, I think they should be doing fireworks/F! more than just the weekends and I don't think it should close so early.
You could look at admission as a cost that should fluctuate with season, but IMO it should stay constant. An off-season vacationer already has the benefit of (usually) less expensive travel and accommodation costs. It's also not like Disney is the only company that does this. Should my local Six Flags charge the same amount for a ticket on a Saturday open from 10-9 vs. a Sunday open from 10-8? Those Saturday guests have a whole extra hour! And actually, Disney has done several promotions in the past to lower admission costs during lower crowd seasons (the "Everybody plays for the kid's price" comes to my mind).
Also you seem to be wanting Disney to accommodate to your personal desires. There are several aspects that prevent what you want from happening.
1. I'm pretty sure the residential area or the city has an agreement with DLR not to do fireworks during the middle of the week because of noise complaints. Even if there's not a formal document, I'm sure a part of it is courtesy to locals.
2. There's simply less demand for nighttime shows during off season. During the times that fireworks and Fantasmic are shown nightly, it's guaranteed that these shows will be packed and tons of people will still be in the parks when they're shown. Same goes for the attractions. How many people are actually still in DL on a September wednesday at 8PM? How many people are in line for Splash Mountain at 8PM on a cold December night? Enough to keep the attraction open for a couple more hours? Probably not.
3. There are fewer seasonal workers during the offseason weekdays, so they can't properly run all the attractions at max capacity. They can't offer as many entertainment options. They can't be open later because they don't have as many CMs running the place.
4. Disney has been doing parks for a while. They know how long they want a refurbishment to take and when they want a particular attraction open by. Thus, the dates are set for the Indy refurb. They probably didn't really take into consider the Space makeover because that happens every year now and it only lasts 4 days. That means the only people affected by the Space/Indy overlap are those guests who are there for only those 4 days...a VERY small percentage of the attendance.
5. Where do you draw the line for changing admission costs? Do you make weekend visitors pay more than weekday guests because they get extra hours and entertainment? What about a weekend during offseason vs. a weekend during Spring Break? What about a weekday with 3 attractions closed vs. 1 attraction? What about guests with multi-day tickets? There are way too many factors that make this process very complicated.
6. Disney is still in the business of making money. They charge the amount that they do because people still pay for it.
Solution? Go during summer! I honestly can't recommend it enough. Crowds are not as bad as some people think, especially with a little planning and preparation.