If you want to fish halibut, it's prime season late June. Plenty of places will take you out in Seward. While I love Homer, and it's an absolutely beautiful drive down especially to Cooper Landing (google pictures of Cooper Landing, Kenai and Homer), that's a 3 hours each way and not worth it to fish there, maybe.. maybe to just get a lay of the land.

Denali: Seward to Talkeetna.. that's 4.5 hours each way. On a clear day, Denali is stunning and may be worth it.. but I'd take the plane and land on the glacier if it's clear. It's a top 10 travel life event. If you can't see Denali like 2/3 of the days, it would be a big disappointment.

Double Musky: Will be a fantastic dinner you'll over eat and not be upset. So good and so unique.

Kenai Fjords National Park boat day/half day trip: I'm suspecting you're gonna be tired of being on a boat, but this National Park is so cool. Sea lions, Dall's Sheep, puffins, a whale or two, calving glaciers. Done it 3 times. It's really good even on not great weather days, other worldly when it's clear.

Kenai: Fish won't be running for a few weeks. I'm sure you could leave from Seward (never left from there) and take a float plane from a lake over to watch bears. I've used High Adventure Air a few times.

Hike: I'm not much of a hiker, but if you're near Cooper Landing, there's a hike to see bears that's mostly a walk on loose rock. It's called Russian River Falls. I've done it twice. At the end, you usually see bears scooping up salmon (from a distance)