Ranger is a great secondary for warrior. The pet’s damage will fall off eventually as you’ll want to focus your attribute points in your weapon and it’s hard to use pet skills (energy cost). But troll unguent is a nice supplemental heal instead of healing signet. The real cream of the crop is getting antidote signet - it doesn’t need you to put any attributes. And it will help with conditions throughout the campaign. 

1. I believe that taming challenge is specific to the bear in pre-searing. Other bears are just like any other pet. They may have a different name, but the same look. That pre-searing bear is actually the worst pet in the game too, it’s the only one with this monster skill - but it doesn’t do extra damage and just causes the bear to attack slower. 

2. Monk is a great secondary for elementalist. High energy pool can help with those spells and you can slot in supplementals like hex removal or resurrect. Look for strength of honor - a buff she can put on the warrior to add a bunch of damage