I think you may find most of your answers yourself …
There is no limit to what you can script depending the version.
The main difference between PRO and CE are here:
The PRO fee is that low that it should not be an issue.
That is lifetime valid per user with one year of updates.
Not limited to the amount of systems you run it on.
FAQ License: QCAD - FAQ
A recent post of the develloper Andrew about upgrading:
QCAD has easy key-in shortcuts:
Although parsing these to the command line as a macro is limited.