the canal part should be doable. i used to live in upstate and would ride the canal paths near rochester often on my go fast bike and on my tourer - it is crushed stone.. tourer had 32s on it. go fast had 23s or 25s.
not sure why they would recommend a hyrbrid. seems it would get uncomfortable after a good while.
compacted gravel can be ridden on 25s and 28s - the 28s will be more comfy.
might want to post this in the touring forum or the regional discussions to pick up some local info.