The Pasayten Wilderness (North of Winthrop) is gorgoeus, has many lakes with nice fish.
Attached is a photo of Remmel Lake & Mtn.
Also not to be missed are the Enchantments out of Leavenworth. Unless you day hike you need a permit to camp (Rangers station).
Inspiration Lake
Lepricaun Lk
Crystal Lk
Colchuck Lk
Both areas are 6-7000’+ altitude and still deep in snow so you’re probably looking in Aug for snow free hiking. But well worth the effort and the wait. Of course theres always snow shoes.
Believe me there are many more vistas there tos see as well.
Be sure to share the photos when you get back.
Bob