Agreed with PeterW about grades. I found 5.10d was around 21.
We spent about a month at squamish a few years back. We loved the cragging on offer in the smoke bluffs and there was plenty of quality single pitch routes on offer, but it was mega busy ALL the time. In comparison the multipitches on the Chief see less traffic, but we still found it busier than multipitches at say Araps. The more flexible you are with your ticklist the more you will enjoy.
The bouldering offered a good change up as it was much less busy and the quality was awesome to say the least.
There is plenty of bushwalking and mountain biking on offer in close proximity to Squamish. I've also heard kayaking near Vancouver is good. Watch out for the occasional storm around Squamish, it can absolutely downpour even in Summer.