So far I'm up to Staunton Island and I've done all of the folowing:
Portland
20 Vigilante
20 Firefighter
Level 12 Paramedic completed
100 Taxi Fares completed
All 5 Rampages
All 8 Unique Jumps
Found all 33 Hidden Packages
All Main Story Missions
Marty Chonks Bitch'n Dog Food Factory missions
El Burro's missions
2x RC Car destrction missions
Patriot Playground
Delivered most of the vehicles to the import/export garage
Staunton Island
All 3 unique jumps
Multistorey Mayhem
A Ride In The Park
20 Vigilante
20 Firefighter
4 Rampages so far
35 Hidden Pakages found
Effectively meaning all I need to do is complete the story missions, side missions and do stuff on Shoreside Vale to get 100%