here is a link to the Lynnwood Parks page on the interurban.
The map below is from that site
Interurban Trail Map
Lynnwood fixed the crossing at 220th and says that they are going to fix the one at 212th. (That will be a major improvement eliminating the detour through the chicane and the park. It remains to be seen how inconvenient they can make the crossing, however.)
When light rail comes to the Lynnwood transit center bicycle access to the train will be important. The construction of the new light rail station will also impact the interurban. One would hope that a better I-5 crossing will get built as part of the project.