Glad to hear you have time to explore more of Oregon after visiting Crater Lake! If you like history and the great outdoors, then the nearest major city, Klamath Falls, is not to be missed. In this sunny town, you’ll find a treasure trove of Western history at the Favell Museum; more than 350 feathered species along the Klamath Basin Birding Trail; rafting and kayaking opportunities; Oregon’s only Arnold Palmer golf course; and so much more.
Otherwise I suggest driving from Crater Lake National Park north on Highway 97 to Highway 138 toward Roseburg (known as the Waterfall Highway). There are many places to stop road-side to take short hikes to waterfalls in this area. From Roseburg, I’d get on I-5 and either head south to Grants Pass to either raft on the Rogue River (stopping at Abacela Winery in Roseburg) or to access Highway 199 to the Coast.
If you’d rather not head north first, drive toward Medford from Crater Lake and stop in Prospect to see the lava tubes along the river at Natural Bridge Trail, and the waterfall at Mill Creek Falls. You’ll drop down into the Medford/Ashland area.
If you’re interested in rafting, many outfitters depart from Merlin, Oregon (north of Grants Pass), for either day trips or multi-day. There’s also hiking along the Rogue River, but it will be hot and exposed in summer.
For the best wineries in this area, I’d head to Ashland, Oregon, where you can enjoy the Shakespeare Festival or just enjoy the dining and shopping in town. Try Dana Campbell for good views while sipping Oregon wine! Then spend a day on the Applegate Wine Trail or Upper Rogue Wine Trail … either will combine beautiful scenery with great wine.