You're not over-thinking it, in fact you're asking good basic questions that should be asked with any rocket you fly.
I did find a file for this one to plug into open rocket, which I can't recommend enough to answer these questions.
When you start getting into motors this size it becomes time to ask more questions actually.
Take all the time you want to think, question, double check, and verify.
All the CTI motors I've checked so far are showing stable numbers, from 1.3 to 1.5 calibers.
The 1 grain and 6 grain being best, as the 1 grain are lightest, and the 6 grain start putting weight ahead of the CG.
However, you really need to keep an eye on you maximum thrust. It's only a 2in 11oz rocket, very easy to over-motor it.
For example, the H410 you mentioned hits 111g and gets close to supersonic. Even the H160 is right at 50g and over 700mph.
Anything over 100n average impulse, regardless of total impulse, gets fast enough to risk airframe failure.
I honestly would only stick to motors up to about 60n of average impulse, and even then just the F's and G's if it were my own rocket.
Also have to watch your delay times pretty close. Due to the speed it'll be hitting, you're going to have a long coast phase.
-Hans
(Ok, I think I've corrected most of my grammar problems finally. Sorry about the continuous edits here.)