Since you will have already had two nights at Crater Lake, I would just drive to the coast after your Wizard Island Day. In the summer days are long, so you will have daylight for the drive. Plus you say the kids do better with night driving. That would make the most of your time. You could do Bandon, or maybe just another night in Florence to not have to change hotels as often. You can't go wrong either way.

It is 90 miles from the south end of Bend to the north entrance of Crater Lake NP. Plan on just under 2 hours to get to the north entrance off Rt. 138. If you can get the tickets for the boat trip online instead of having to go to the visitor center to pick them up, you could go to the head of the Cleetwood trail and hike down for your boat trip to Wizard Island. After climbing back up the trail after your boat trip you will not feel like driving more than 60 miles IMO. Driving from either entrance of Crater Lake NP west to the coast is best done in the morning with the sun behind you and being well rested.
Unless you are big on golfing, I think there are better places on the Oregon coast than Brookings (personal opinion).
If you go back to the north entrance to exit the park, the trip west on 138 down the Umpqua River is more scenic than the route to the coast from the south entrance. If you go north on I-5 from Roseburg and then go west on the western section of 138 to Rt. 38 west you will come out to the coast at Reedsport. About 5 miles before Reedsport, stop at the Deans Creek viewing area. you can usually see a few Roosevelt elk from there.
How many days are you spending in the Bend area? Do you begin and end your trip in Portland? While in Bend see the High Desert Museum and the Lavalands Visitor Center.
By the way Welcome to Fodors!

The drive from Crater ake to Roseburg on OR-138 is very scenic, with several waterfalls: http://www.co.douglas.or.us/parks/br...pqua_river.pdf

Take OR-42 from south of Roseburg out to the coast. IMHO Bandon is the jewel of the Oregon coast...do not pass it up. Bandon Baking Company - Home

Tomfuller--What??? The hike back up is only a mile. Yes it is 700 ft gain, but driving after that is not difficult at all, IME. We have done this countless times and never even thought about it until I read your comment.

Is your trip in the early summer or later summer? Early in the summer and there might still be some snow. I have seen the north entrance open on July 1 with a couple of the roads having snow on the edges.
In late summer there is a chance that there will be forest fire smoke that will cut your picture quality.
Try to enjoy the beautiful Oregon scenery in the daytime instead of driving through it in the dark. You are much more likely to hit a deer or other wildlife in the dark than in the daytime (true in most areas of Oregon).

You will be fine, and not driving in the dark. Sunset that time of year is around 8:30, so plenty of time for driving with daylight. If this were my trip,I would skip Bandon for the reasons you mention.

I really dislike driving west in the late afternoon. If you want a little head start going west from the north entrance of Crater Lake, you should consider the Diamond Lake Resort or the Steamboat Inn along 138.
The Inn is on a bluff over the Umpqua River. There is also a place along 138 where you can see colliding rivers.
One of the most historic things about Roseburg is the Roseburg Blast which happened one night many years ago when a dynamite truck was parked next to the lumber yard that had a fire.

Another vote for Hwy138. Many nice waterfall hikes- most of them pretty easy. My favorite hike is Watson Falls and Susan Falls. I am sure sure you can get a map at the lodge. If you stop in Roseburg, the McMenamins restaurant is a good stop- in an old train station and just across the street from a wine tasting spot which features many of the wines in the area.

http://www.co.douglas.or.us/parks/br...pqua_river.pdf

Hey, if you have two days at Crater Lake, then I would head out to the beach after the hike. I'm not sure you want to spend a lot of time along the way. I'd probably get a quicker meal in Roseburg if you decide to drive to the coast. I think there's a Sonic there, which is kind of fun.

Honestly I'd do an extra day in Florence. One fun thing to do in Florence if you're there two nights, is to go to Honeyman State Park. The lake has an old fashioned diving platform out in the middle and a lodge. And of course, go to the beach.

Or the other thought is that during the day you go from Florence to Seaside, you could stop along the way in Newport. The Aquarium is excellent there, especially the shark tank. Or the Hatfield Marine Science Center.

https://www.timeanddate.com/sun/usa/...th=8&year=2019