There are three Wildcat Mountains in Oregon, so be sure you want the North Coast version south of Highway 26. The road to the trailhead is short and easy in any passenger vehicle, there's a good spot to park, and summit is in the Tillamook Forest, although the shortest access crosses private timberland. The hike is about 1.5 miles one way, and 400 vertical feet gain. This description I consider the 'no bushwack' version.
Cornell Mountain, Portland Oregon. W7O/WV-090
Easy parking on Penridge Rd. Definitely a pavement activation. Quiet neighborhood with plenty of folks walking their doggos.. I really wanted to throw a wire up and work CW but didnt see a spot that wasn't private property.
So out came the Yaesu FT-60.
146.520 worked well for me and I made 4 contacts relatively quick and easy which was nice because I really didnt want to disturb or raise any suspicions with the fine folks from the neighborhood that were out and about with their dogs.
Whatatis Peak is directly North of the Hanford Reach National Monument. From Richland WA to the summit is just over 61 miles. You can drive very close to the summit, only the last little 1/4 mile kick up to the top peak is really treacherous. There is good parking at serveral locations off the access road to pull over to complete the summit on foot. I did a 2.5 mile hike to the top.
I activated my first SOTA summit here. Nice views and plenty of tall trees for your wire antenna. Parking is great. Plenty of room along with several picnic tables. Restroom facilities were available and clean.
Highly recommend for your first SOTA Summit.
https://oregonstateparks.org/index.cfm?do=parkPage.dsp_parkPage&parkId=77
Nov 2, 2019 was the perfect day for climbing Mt. Carrie. The weather was cool and clear. Some snow up above Heart lake, but the Cat Walk (the unmaintained trail and scramble east of Heart Lake) was free of snow. That area would be very challenging with snow, and an ice axe and crampons would be a must.
I like big buttes, and I can not lie... 
I don't have much to add that K7NIT didn't already cover in her excellent report.
Hawk Mountain was an easy 1 hour hike to a summit with great views of Mt Jefferson and further south. The trail is well maintaned and there were Huckleberries galore that may delay your QRX.
Take forest road 46 (paved) to forest road 6350 and 6355 west to the trail head at 44.84062, -121.94718. Forest road 6350 is a well graded gravel road that is rated "Prius-able". The Hike is 2 miles each way with an elevation gain of 789'.
3780 Top Loaded Mountain is an easy 4 point summit in Washington. I was able to activate this summit while out camping with my family at nearby Chehalis RV and Camping Resort. Looking for summits nearby to activate using my SOTA Spotter app 3780 Top Loaded Mountain and Rooster Rock showed up and both had been activated already. Usually that's a good sign that there is a good way to the summit.
Rooster Rock is an easy 4 point summit in Washington. I was able to activate Rooster Rock while out camping with my family at nearby Chehalis RV and Camping Resort. Looking for summits nearby to activate using my SOTA Spotter app Rooster Rock and 3780 Top Loaded Mountain showed up and both had been activated already. Usually that's a good sign that there is a good way to the summit.
Crater Peak is a pleasant trail hike in Crater Lake National Park. It's been covered in a trip report by Phil-NS7P, so this should be considered a supplement. It's about 6.4 miles round trip, and although the sign at the trailhead says 765 feet of gain, that's net - the gross is more like 1,364 feet with all the ups and downs along the trail.