Great introduction to Vancouver. The Fish Head portal of the aquarium needs drift if you do not plan to get inside. There is a pedestrian-access-only road and you can walk in to see if can get access. If there is one mission that is not 24/7, then it should be the aquarium.
All other portals are fairly accessible. The waypoints are carefully configured and I've learned a lot from the extra information on Vancouver.
The MD Series is awesome. I spent a whole day around Victoria Harbour and just wished there can be more.
Every portal is accessible 24 / 7 and you don't need any drift, just hack and enjoy the harbor view.
As of Apr 2019, the route alongside the harbor from Golden Bauhinia Square to Central and Western District Promenade is still under maintenance, you would have to detour to Convention Ave and Lung Wui Road for pedestrian access to Tamar Park. It is roughly 2km walk without available public transit.
Personally I recommend ferry as one of the transport between missions. I began with Lei Yue Mun, ferried to Fireboat Alexander Grantham, Shau Kei Wan Typhoon Shelter, then ferried back to Kwun Tong Promenade. The mission is so carefully chosen that you can finish the series via zigzagging between coasts.