AK's nighttime issue is definitely from lack of indoor attractions. While Pandora will add two more indoor attractions that operate from open to close, the park will still be significantly behind since TDO never bothered to properly address expansion for the park.
In 18 years, the park has added a river rapids ride (that should have been ready by opening day), a carnie mini-land (instead of the Excavator coaster or family-friendly dino dark ride rumored) and Expedition Everest (admittedly a great addition to the park, but the lack of attractions keeps TDO from fixing the Yeti since they can't afford to keep Everest down for extended periods)
If TDO wants to fix AK, they'll need to add a few dark rides/coasters. Lion King and Jungle Book are two obvious examples for dark rides in Africa and Asia. Dinoland could use an alternative option for kids too short/scared to ride DINOSAUR (if only Good Dinosaur earned more than peanuts
). Rafiki's Planet Watch could include a retro Epcot-esque dark ride focused more on teaching about conservation.
There are opportunities to fix the nighttime issues, but the question is whether TDO will find the time in the next decade. I'd say no, because Toy Story Land, Star Wars Land, DHS's parking overhaul, the Tomorrowland revamp and the Epcot overhaul are likely going to dominate the next decade. If AK gets any expansion plans, it won't be until at least the early 2020s IMO.