Hello, I live in salem oregon. I personally am not a fan of portland but there is a LOT to do there. If you have children they have OMSI (
https://www.omsi.edu/) But at OMSI they do have OMSI after dark for adults only. (
https://www.omsi.edu/calendar?start[value]=&end[value]=&keywords[0]=351&keys= ) I have not gone to OMSI after dark but I want to. If you can avoid downtown portland during lunch time that would be best. Parking, in a parking area, which does cost money, and walking around is the best. Just remember it will be cold and other raining or snowy around that time. We are sometimes dry but the last few years it has been wet.
The pearl district is by far the best place for me. (
http://explorethepearl.com/) It is more of the art side of Portland. If you are staying in a hotel, I would recommend not staying in the rose district also know as downtown Portland, the prices are a little more, but if that is not a problem them it would be more convenient to walk around.
I have not been to the breweries up there but I have family members that swear by them. I have not also been to many of the parks up there. But if you are welling to go outside of Portland, there are many other great things not to far away.
Down in Salem we do have wine tastings, the Willamette Queen river boat (
http://www.willamettequeen.com/), and the historical Reed Opera House (
http://www.reedoperahouse.com/)
Siverton has the silver creek falls (
http://oregonstateparks.org/index.cfm?do=parkPage.dsp_parkPage&parkId=151) and the Oregon gardens (
http://www.oregongarden.org/)
Woodburn has the woodburn outlet which has more higher end stores (
http://www.premiumoutlets.com/mall/woodburn/stores)
Up on mt hood, I believe they will still be open in April/May, we have skiing and inter-tubing.
Out by the coast there is a small town called Grand Ronde that has Spirit Mountain Casino. Even if you don't gamble they have an amazing buffet. (
http://spiritmountain.com/)
Oregons beachs are amazing, but cold so bring a jacket if you go that way. During low tide you can get handfuls of shells and eat at mo's that get their sea food from the waters outside of the restaurant.
Other things in Portland I didn't know about but I am not making a list of things to do aswell (
http://www.movoto.com/guide/or/things-to-do-in-oregon/) HOWEVER I WOULD NEVER TELL ANYONE TO GO TO VOODOO DONUTS!!!!! everyone here in Oregon swears by them, that their is no place better but they have had 4 failed health inspections all do to rat droppings. I have family that goes there but I personally would never eat from there.
At the moment Portland is underwater per say. They had some extreme flooding and record rain fall so I know that the buses and Trimet are down. They were effected by the last, much smaller flood and were in repair when this large flood hit. I don't know when the rain will stop, or if it will. So you will have to keep tabs on that. I have heard that it is pretty cheap and the tri will take you all over town and even into other parts of portland and washington. The buses will get you to Salem and from there you can get to any place I have mentioned.
LAST BUT NOT LEAST, my favorite thing to do in Portland. Going to the Lloyd center for some ice skating. (
http://www.lloydcenter.com/) It is a mall with a full size ice skating rink inside open all year long.
I hoped this helps out.