My wife and I moved to Bellingham in the summer after spec'ing it out for 1 year before pulling the trigger and moving. We love living here so far. Before moving to Belilngham, we lived in Vancouver, WA for 1 year and for the year before that we were in the northwest of Portland.

In my experience, Bellingham is a place to go once you've got life "figured out", aka, have a job, money, or lifestyle to enjoy Bellingham. Bellingham, IMHO, is very lifestyle focused. There are two large populations of retirees and students. My wife and I are in our early 30s, and there are plenty of similarly situated in life here in BHAM, though most have children.

Based on the OP's criteria, I'd argue that Vancouver, WA is a better choice for them at this stage in their life. Vancouver is just across the river from Portland, and thus, is a regional suburb of Portland. The Portland region has roughly 6 million people, and that equates to a lot more job opportunities, especially in the tech industry. If the OP's partner is use to working in datacenters, some of the world's biggest datacenters are in The Dallas.

As a recent buyer in the Bellingham and a renter in the Vancouver housing market, it was my experience that the cost of a comparable home in Bellingham is much greater than in the 'Couve. Moreover, in Vancouver, one can take advantage of the sales-tax free state of Oregon very easily - and save some more money.

Vancouver, WA has a bad reputation for being very "'murica", especially from Portlanders, and IMHO for the most part they are right. However, when I lived there (and even though I knew it was temporary), I found that it actually was a great place to live, if you can look past some of the common criticisms of Vancouver. There is a good community there and tons of cool places to hang out. The cost of living is cheaper than Bellingham and there are more opportunities for pretty much everything.