While most fans of the 3 USL-1 teams that participated in the Cascadia Cup hope to not see it return until all three teams are in MLS and base the winner of the Cup off of clubs' performance in the regular season, I wonder if there is a way that the Cup could continue as a preseason tournament that would grow the sport throughout the region and make some money for all teams that participate.
The Charleston Battery host a preseason tournament with 3 invitees from MLS that has helped the Battery have a rivalry with DC United and get locals caring about their club before the season starts.
These 3 are the original members of the Cascadia Cup tradition.
Seattle Sounders FC - MLS (2 time winners in USL)
Vancouver Whitecaps - USL-1 (3 time winners)
Portland Timbers - USL-1 (Never won)
The following teams play in the states/province with the Cascades as their backbone
Vancouver Whitecaps Residency
Portland Timbers U-23
That's 13 teams total, all which could use training matches and some income. Televising matches in the local markets would generate a little bit of income for all involved teams. Spreading the tournament out between a total of 3 sites would also spread the wealth from attendance. Inviting two teams from outside of the region would create a 15 team competition. Teams that play in "summer" leagues could come from MLS, USL, or maybe even the A-League, J.League, Norway, Sweden, etc.
I would suggest a Group Stage of a single match round-robin format hosted at PGE, Swangard and Starfire. The winner of each Group stage and the best of the second place finishers would advance to the semi-finals in PGE and Swangard with the Cascadia Cup Final at Qwest. Switching the Residency and U-23 teams would mean that they wouldn't face their sponsor team unless they make the Semis, which would tend to avoid a potentially embarrassing situation for the USL-1 teams.
Here's a sample of the Group Stage
Whichever of the Timbers and Whitecaps finished at the top of their league would get to choose to hose the winner of the WA group or the #2 overall. This allows them the choice of hosting a better team and getting more money, or more likely making the Final.
There are some significant benefits for this tournament continuing the tradition of the Cascadia Cup. Each team would get four matches and after 9 days (matches basically every other day) the Semifinals could be hosted on a Sunday Night with the Final taking place the next Friday Night. This could all be done in late Feb / early March in order for the Final to take place on the last Friday before MLS Opening Kick. It would give a small revenue stream for all teams taking part, useful training and give the entire region a reason to watch domestic soccer when it would not compete with the NFL, MLB and the NBA and NHL would be in middle of their long seasons.
But it would also be a departure from a long tradition, and would be difficult for the varying teams and leagues to agree to it.