You're not going to get a lot of responses on this site unless it's about going Asia or Vegas

I'd try the thorntree forum:
https://www.lonelyplanet.com/thorntree
Countries to avoid? I've been hearing Venezuela in the news a lot lately for the wrong reasons: Riots, high crime, government sanctioned anti-Americanism (may or may not affect Canadians). Also with Honduras (highest murder rate in the world)
Must sees?
I went to Peru in 2009 and thoroughly enjoyed it. You can see my thread with pics here:
http://www.revscene.net/forums/563077-peru.html
My gf also went to Colombia and raved about it as well. Great people, food, and architecture:
Don't know if you're including Mexico in "Central America" but I visited in 2013 and went to Mexico City, Puebla, and Oaxaca. All great places and off the usual tourist trail.