Below is my laundry list of what ST or it's successor needs to do, listed in the order that I think it makes sence to do them. Stations mentioned on a specific line, are not ment to be considered the total list of stations, each area should have input on the locations and number of stations on it's segment.
1. Eastside Railroad Purchase and improve the existing rail corridor on the Eastside of Lake Washington. A 3 year pilot service could be up and running from Snohomish to Renton in 3 months for $10M offering service during the daily commutes (in both directions) at an initial speed of between 30 and 45 mph. Fully upgrading the line to support all day, 60mph service between Everett and Tukwila Sounder Stations (and along the Spur between Woodinville and Redmond) would cost somewhere between $300M and $500m, and could be implemented in such a way that the pilot continues to run during the upgrade. (this solution provides a complete rail service loop around lake Washington for approximately the cost of one to two miles of Link Light Rail.
2. Hi Capacity Buss Links Run high Capacity Buss service along I-90, 520 and 522 connecting Seattle to the East side Railroad, where possible dedicated lanes may be appropriate
3. Upgrade Sounder corridor. Add one additional rail along the Sounder corridor from Tacoma to Seattle, and if possible from Seattle to Everett. This rail will allow all day bidirectional service from Everett to Tacoma. The east side line would also be able to use this expanded capacity to either continue its service (from its current termination in Tukwilla) all the way south to Tacoma, or north into Seattle. (possiably have alternating trains have alternating source/destination on the south end)
4. Sounder Service extension Expand Sounder service (some of these extensions would be better serverd with DMU's as opposed to the current Sounder rolling stock) South of Tacoma as far as Olympia, and north of Everett to as far as Mt. Vernon, East from Everett to Monroe or Sultan. East from Puyallup along existing and former BNSF ROW to Orting and Enumclaw (future expansion from Enumclaw could follow old rail ROW all the way to Northbend and Snoqualmie , with a possible alternate alignment on the Stampede pass line into Auburn
5. Link Tulwilla to West Seattle Link Light rail from the Tukwila Sounder Station, and Southcenter mall, joining the existing Link line along 518, and diverging after the Tukwila Link station, west along 518 to Burien, then North ultimately along 35th or California through West Seattle, with a possible Fauntleroy terminal stop. It may be possible to connect the north end back to King Street station via a DMU service or a dedicated line along the edge of the freight yards. this should where possible also be at grade. An alternate posability for the north end of this segment would be to cross under Elliot Bay in a submerged tunnel like the BART TBT, with a station located at teh downtown Ferry terminal, and then tunnel under Maddison past the buss tunnel, and up to at least Seattle University
6. Link UW to Ballard Expand Link from UW West along the North side of the Ship Canal and Lake Union terminating at a new Sounder/Link station.
7. Eastlink build the Bellevue Redmond and possible the Bellevue Mercer island portions of Eastlink again avoiding tunnels and viaducts wherever possible.
8. Eastside Rail Expansion (north west) Expand from Woodinville along the I-405 corridor (mostly in the median) to Alderwood with stops at Cascadia Community College, Canyon Park, and Alderwood. Future expansion could continue west to the Sounder Station in Edmonds. The expansion Woodinville to Alderwood would be at grade in the median of I-405 but might require a tunnel to reach the median. the extension from Alderwood/Lynwood to Edmonds would probably require a tunnel along most of its run.
9. Eastside Railroad Expansion (south east) Expand the East Side railroad from Redmond to Issaquah on the rail banked corridor that currently houses the East Lake Sammamish Trail (move the trail route to the West side of Lake Sammamish. Future expansion from Issaquah could go East along the original RR ROW to Snoqualmie and North Bend, and South on new ROW to Maple Valley eventual joining with the Stampede Pass BNSF line and into Auburn. All of these expansions would be at grade.
10. Link expansion Expand link from UW to at least Northgate. Extend Link from SeaTac to SeaTac Mall. All link extensions should concentrate on at grade alignments, and avoid tunneling and viaducts wherever possible.