Great start. This thing looks awesome! Thanks for your efforts with this.
One thing you might want to add is that if you have a social club account linked to your gamertag you can go the GTA V section of the social club website (in real life, not the game). If you look under Career, then checklist, it shows you which missions, pastimes, random events, etc you've done and have yet to do. There is even a map which shows the collectables you've gotten.
This should be the link