1)I'll second Pittock Mansion/ Portland City Grill for the views. Metropolitan Tavern across the river also has a great patio facing the skyline & the top floor of the parking garage on 9th & Morrison has some good views if youre not against some mild trespassing
2) I'll add Sunnyside/Hawthorne to the list of cool non Downtown neighborhoods. Checked out Foxtrot on my last visit & was blown away. The area around Hawthorne/34th is also packed with great stores/restaurants
3) I feel like Portland has leaned so far into fusion cuisine thats its just kind of standard for all the food now. I would recommend Javelina though which features indigenous foods fused with classics from other cultures like 'frybread tacos' or 'elk shoulder benedicts'. It's near the airport so probably worth hitting up on the way in or the way out
There's also Kann which is a Haitian fusion spot that got featured on a bunch of cooking shows but it is SPENDY & probably hard to get a rez for this late in the game
Kilo DCofi is Downtown and features spiced Mexican Coffees mixed with more standard espresso drinks
Other than that, just go to a food truck pod and you will find something great and unique. The Korean BBQ burritos from 'Korean Twist' at the Midtown Beer Garden were always a go to for me.
4) If you have Saturday off, I 1000% want to reiterate the Saturday Market which takes place near Ankeny Plaza/ Waterfront Park every Sat morning into early afternoon. Probably the spot to get the most consolidated Portland experience in the least amount of time