RC Markers are really useful since they can be accessed via script so users can make a large number of changes, but if we can`t influence the root parameters of generators we are limited just on transforms or we have to do some heavy nesting to overcome this limitation.
The fixed field number is ok. If the user can set this number in the Base Object Customization menu, even better.
For the active parameters, I would like to see them all working but for the priority, it would be parameters from the General tab: X/Y Sizes, Offsets;
for L1S: Reverse/Mirror/Flip;
for A2S: Z Rotation, Expand;