If you want ground-target effects, pretty much your choices are IS Boxer or HKN.

IS Boxer is $36/year, as a subscription; slightly longer if you mention a referral... you can run up to five systems at once on the same subscription.
It has easy and accurate mouse broadcasting, which can turn on with the hotkey for the Hurricane (for example) and which turns off once you click for a target area.
There is a bit of a learning curve, but once you get the idea of how it works, it is very easy to configure to do exactly as you want; it is highly flexible and probably the most powerful software for boxing.
The automatic FTL assist is huge, as that can be a pain to set up with other software options.

HKN is free, which is a rather good price.
It is script based, which means a bit harder to configure for most of us.
But there are a lot of scripts out there, depending on your needs.
For example, you can have one which will turn on mouse broadcasting on a keystroke and off on another... and then go with Keyclone for the remainder of your boxing needs.

Keyclone is $20, for a lifetime license and is good on one computer.
From a press this key, and every other client gets the same key perspective, KC is as good as anything.
You can blacklist keys to not broadcast, or whitelist keys so only those broadcast... not nearly as flexible as Mapped Keys in IS Boxer, but definitely workable.
Setting up FTL assist is possible, but not simple; the first FTL was developed with KC.

I don't know much about Game Commander Pro, but GCP is another option out there.
Auto Hot Key, is in the same category; I don't know much (this is script based, like HKN), but its mentioned here and there.
Octopus, same deal too.



I'd go with IS Boxer personally.
You can do a 7 day trial.
And there is also a 14-day money back guarantee.
So, a lot of time to decide if you like it or not.