I have a road bike with a Tiagra 10speed groupset 50/34 11-32 and find it a bit too high for the roads around here (also in BC). I'm just about to buy a 650b wheelset for it and am considering gearing as well.
The easiest, quickest change I plan to try is to swap in an 11-36 cassette. The derailer should be able to handle that without modification. The specs for derailers are usually a little conservative. After that It seems one will have to start looking at derailer and/or crank swaps. Before that I will probably use a
Wolftooth derailer adaptor to extend the range of my rear derailer and add an 11/40. When you go that wide range though you have to start being aware of cross chaining.
Ps. I've ridden several sections of the Great/TCT trail in the lower mainland upper Fraser Valley. It's a real mixed bag of conditions