Honestly I prefer Bonshaw to Brookvale. Loads of flow to be had if you take the right route. (Seems like having a local tour guide helped). You’ll have no lack of climbing there. I would recommend doing PB and J and Skull trail 2x or more. It’s a quick loop but worth it. Attached is my trailforks from Bonshaw and Strangathy. This is a route provided by Bruce Mac who is considered a tour guide by bike PEI for MTB?
Also make sure to ride everything at Brookvale 2x or more. Why? Because it is amazing, that is why!
From what I know stay out of Secret Snake. And St.Catherines also sounds pretty hard.
You wont regret it at all. The trails are wicked.
Food suggestion. Thai Pad food truck in Charlottown. Trust me I love food.
Have a great trip. Trust me you’ll grin ear to ear when you realize the island is a huge pump track.