Karw,
I think also that this simplicity thing has two faces, but I try also to keep a little pun in my way of looking at things.
In this sense AIM BTB is on the one hand simple(executable right away without needing to study the concept to any great depth, and by ignoring the SAFE Retard Function I made it simpler yet(from am execution point of view).
The other extreme is to try to understand all the implications and consequences of the simple version(4 parameters). That in itself is not a simple matter and requires a lot of work.
With respect to your statement that AIM BTB being a 4-parameter system(ignoring the CER as a parameter for now) I would say that AIM BTB is actually a 2-parameter system: the Min Buy and Min Sell are(were) essentially only filters that were dependent on external factors like broker fees and are as such not system parameters but operational boundary conditions(they did not affect the AIM functioning in it's operational regime).
Now, as you make the Min Trades also functional within the normal operational regime in which normally the SAFES determine the GO-NOGO boundaries then the Min Trade criteria takes on the dimension of a Resistance apart form the SAFE Function(Trade Retardation). In what you say it appears that you have make a significant(but subtle) switch(AIM By The Other Book):
Min Trade can set the traditional, externally determined, boundary condition and the SAFE functions as Resistance as well as Trade Retarding Function(Min. Trade is smaller than SAFE).
The other way is that the Min Trade determines exclusively the operational regime based on internal factors and the SAFE functions only to Reduce or increase the Trade Amount( Min. Trade is greater than SAFE).
This is interesting indeed: you can now use negative SAFES to increase the aggressively for low volatility stock! But in this you need to pick an other name: the name "SAFE" no longer signifies what it does.
Essentially the SAFE you described works the same as the aggression function in Vortex, except that in your AIM you still work with the asymmetric PC.
It would appear that various AIM derivatives migrate towards the Vortex Concept. I consider many these new ideas as collateral compliments in my direction.
:-)
Conrad