1) Adrenal Defense - RMCII,23. Does the bonus per level actually apply to this skill ? (at levels 10-20 for example you can put just 1 costly rank in the skill and still benefit from a decent increment in DB coming from the bonus per level)
This skill adds its skill rank bonus to DB. For ranks 1-10, that is a +5; for ranks 11-20, that is a +2, etc..
In RoCoII, Adrenal Defense is listed as a Concentration skill, and thus if the profession gets a level bonus in that category of skills, so would Adrenal Defense (making it much more powerful). And don't forget that level bonuses stop at level 20.
2) Tumbling Attack - RMCII, 41. Once you have 100% in it you basically always attack with full OB and compel your target to make an orientation roll or be stunned ? It seems exceptionally powerful to me.
Once you have a Tumbling Attack skill bonus of 100 or higher, you get to use your full OB, yes.
However, that still requires that you make a
successful Tumbling Attack maneuver roll, and the Difficulty of that maneuver roll is determined by the GM.
An Orientation roll is nothing more than a Perception maneuver. And it is the GM who sets the difficulty of this maneuver roll as well.
This means that a foe who sees you Tumbling towards him is likely to have to make a Routine Orientation roll, where if you Tumble towards a foe from his rear flank, that foe might have to make a Very Hard Orientation Roll.
As for the foe being stunned, he isn't really stunned, he is just treated as being stunned as a method of handling the "surprise" since you caught him "flat-footed".
