Tested - 10 tries, up to 8lvl - Crac had 50% of getting armorer and 70% of not getting crap @ 2nd up; Taz - 70% (off), 80% (ngc).
There are only 250+ trees for each hero, so 10 is too few to draw conclusions.
The probability of defense 6 for Barbarians and attack 5 for Swamp creatures is a well-known fact. To judge whether this probability applies specifically to Crag and Tazar, you need to check a much larger number of trees than 10.
