Yes, convert the empty office buildings to apartments or condos. That will help a little, but commercial real estate tenants tend to pay more in taxes than someone renting an apartment to live in. More businesses downtown mean more tax dollars for Multnomah County.
Ideally, you have a nice combination.......people who live and work in the downtown area.
I believe we got on this topic because of how it relates to attracting sports franchises. (i.e, selling luxury suites to businesses in Portland compared to SLC) They don't need Fortune 500 companies, but they do need to reverse the trend of businesses moving out of the area.