It would be kind of silly if you couldn't group up devices like that. If you think about it, modern networks work very much like this. Take a modern-day setup. We have companies with servers that all slave a number of computers to themselves. Those computers, in turn, will slave other devices (such as flash drives, mice, keyboards, monitors, ect.)
Your rational is correct. You can, indeed, create groups of devices, slave them to a commlink, and then have the decker slave the commlinks to himself. This creates a mobile PAN (personal area network) mesh that the decker can more easily police and protect, since he's the first thing an enemy hacker has to get through. There are, of course, problems with this setup.
The biggest flaw to this setup is what happens when someone DOES make it through your detection and firewall unchecked? The answer? They now have EVERY piece of hardware your entire team owns at their fingertips. And until you can get them out of your node, they can choose to screw with any of the devices. Normally, if they want to hack the street sam, they'd need to be within range and hack their commlink separately. It's easier, but that's multiple points of failure, since the enemy hacker can't get to anyone else on your team through the sam. With you protecting the group, you're more likely to catch any intrusion, but if you fail, the enemy hacker now has three marks on your entire team and hilarity can ensue (read: bad things for your team).
Generally, you want to protect all of your party members and slave all of their devices to your deck. Period. There is no reason NOT to do this, honestly. The chances that you'll miss a hacker in your system are pretty low anyways, and even if you do miss them, rebooting your deck will sever the connection and erase the hacker's marks on your deck, forcing the enemy hacker to have to start again on someone else's device.
Yes, programs that are run on the RCC are shared between all slaved drones. Since it's [Weapon] Targeting you need to run one Autosoft per weapon type used. Since you're only using Ares Alphas, you only need a single Autosoft for this purpose.
Note that you need to run all of the Autosofts on the RCC if you want this benefit, so if you want to run the Evasion autosoft for all your drones, you'd need to run 2 more softs on the RCC (one for each model) and for the Maneuvering, you'd need to run 2 more autosofts on the RCC. Also for every Autosoft you run on your RCC, one less point of Noise Reduction is available, so choose the programs wisely...
SR5 p.267, Noise Reduction & Sharing (emphasis mine)
The Sharing rating is the number of autosofts
you can run on the RCC that simultaneously run on all
slaved drones at the same time. One caveat: if a drone is
running any of its own autosofts, it cannot benefit from
the RCC’s autosofts.
The total of [the Sharing and Noise Reduction ratings] cannot exceed the device
rating of the RCC.
Best Answer
A drone, while kind of squishy, is not totally unable to pat it's head and rub it's tummy (so to speak). It doesn't need an autosoft for most of it's tasks. However, it does seem to need one for firing weapons that are attached to it. You'll need a Targeting autosoft just to make the roll for a drone (note: this autosoft isn't needed if you're jumped into the drone).
As a rigger, you have to choose what to do for drones. Not only can they load up their own autosofts, they can use yours on your RCC as well. The rules do state that a drone can only use the RCC programs if it doesn't have it's own loaded up, but I think it would be easy enough to handwave letting a rigger disable drone programs to override with RCC programs (talk to your DM, your mileage may vary). So, what I would do is this:
Have three groups of drones: air surveillance, ground surveillance, and support. Air surveillance drones should have a good Clearsight and a good Stealth autosoft (can't remember what the actual autosoft names are). Then, have a Targeting autosoft for them on your RCC, in storage, ready to load up and run when you need it. Do the same with the ground surveillance ones, but I would ready a Maneuver autosoft for them rather then a Targeting one. Finally, for the combat drones, load up a Targeting and Clearsight autosoft and ready a Maneuvering autosoft in case they are going up against things they can't kill outright themselves.
When we get the Cannon Companion or Arsenal book (which I believe is the first splat book slated for release) we'll have a lot better ways to trick out and customize your drones. But for now, use them safely and try to overwhelm opponents. If you can't do this, use your combat ones to Covering Fire and zone control while your actual street sams flank or run away.
First and foremost as a rigger, you are support. Your job is not to blow away targets. It's to light those targets up and inform your group so they can do it that much better. And have autosofts ready to load up into the RCC to get them out of danger.