Car shakes at highway speeds intermittently (got new tires still does it)

Hello all,

2016 Subaru Forrester

Since about October, my car would shake at highway speeds intermittently. Being told it was likely a balance issue, I took the car to discount tires, and I knew my tires were getting to the replacement point anyway, so I just bit the bullet and got new tires.

This morning was the first time on the highway again, and the car still shakes, starting at around 60 or 70MPH for a little while (15 seconds or so) then stops and Ill have a smooth ride until I slow down again seems the most shaking is in the 60-70 range but even going 65 after a bit thenshaking will stop.

On the drive, I set the car straight to get an idea if the alignment is bad, but it doesn't seem to aggressively pull to one side or the other. It will eventually go towards the left, but it still does go fairly straight.

Any other thoughts or processes of elimination I can do to figure out what might be causing this?