Even without Infinity Threading, you'll have way more dice as a Command rigger than a Jumped In rigger.
See, that's why I'm calling munchkin: You don't even bother to address my claim that both build can reach plenty enough dice, but merely insist that your pool is bigger.
Both jump-in and Command riggers can easily start with 20 dice right out of chargen and reach 30-something with a bit of Karma and Nuyen. Once you have reached that point, what do another five dice give you? In those few cases where they are needed I'll simply use Edge, that's what it's for.
Just for reference, the gunnery pool of a jumped-in rigger
Response 6
Gunnery 6
Specialization 2
Hot Sim 2
Smartlink 2
R5 Machine Sprite running Diagnostics ~3
That's already 21 dice with hardly anything the player needs to bend over backwards for. Not sensational, but neither something that's "bad and you don't want to"
Further improvements
Control Rig 2 (fill the remaining Essence with other useful stuff, Damage Compensators are nice for example)
Max out Sprite assistance, another 3
Immersion Echo 2
Active targeting (roll a Perception test vs. target's Agility, add hits to dice pool)
Response 6 is costly. You can't start with it without Restricted gear, and it adds 8000Y per Drone to your costs. Ouch!
Control Rig 2 eats essence and you're a Technomancer.
Active Targeting is silly. Spend a simple action to get net hits to your attack test? Just shoot them with a Wide Burst, and then they get a penalty to their next defense check for being wounded.
Now, let's compare a Command technomancer rigger. We're not using Infinity Threading but we are going to use Threading.
Command 6
Gunnery 6
Specialization 2
Hot Sim 2 (Control Device is a matrix action)
Smartlink 2
R5 Machine Sprite running Diagnostics ~3
Codeslinger: Command Device 2
OK, now lets get to boosting Command -
without assuming Infinity Threading. Resonance 6 plus Software 4 plus Analytic Mind 2 is 12 dice on threading. Resonance 6 + Intuition 5 is 11 dice on fade resist. That's enough to quite reliably thread up 2 hits and soak 2P; you have a very low chance of getting insufficient hits for that, so no Infinity Threading doesn't stop this.
You can easily Register sprites in downtime, so long as you stick to ones that can't do P damage to you for trying. All you really need is a rating 4 sprite for this, but if you want you can probably get a higher rated one. It can Assist Operation you up another 4 when you need it; this does eat up services and is short-term, but it will last an entire fight. So let's look at your dice pool: 23 dice, 27 with the sprite's help - and we didn't spend 8000Y per drone upgrading everything with Response 6!
Further improvements
Max out Sprite assistance, another 3
You can buy your Resonance and your Command CF up higher
Of course, you could argue this is somewhat overkill; however, this is assuming you're doing something you are heavily specialized at. Even with NO rating in a skill - such as if you have to pilot a Watercraft or something - the command rigger can get Command 8 - Defaulting 1 + Hot Sim 2 + Diagnostics 3 + Codeslinger 2 for 14 dice, which is quite impressive - and unlike the jumped in rigger, who cannot get any better, in emergencies the command rigger can thread higher and risk a point or two of P damage, and can use registered sprite services to get up to 18 dice on tests for which he lacks the skill.
Finally, the command rigger is
cheap. You don't need expensive command and sensor upgrades for you drones. You don't need to risk your life by being jumped in with hot sim. You can run an off-the-shelf, unmodified vehicle that you've never seen before and be extremely good with it. The Jumped-In Rigger needs to upgrade each and every vehicle and drone and has to jam Rigger Adaptation on everything - all this stuff adds up fast.
Incidentally, you might be wondering "so what IS this infinity threading abuse I hear so much about?" The answer is that it's only really good when you can jack your Fade Resist up really high and have a good doctor and a mage on-hand. You can then wait until you get something crazy like 6-7 hits, suck a huge amount of damage, and get medical attention. This is a good trick for getting a CF you don't have up to 12, or for getting a CF to 12 long-term without needing a sprite, but it's hardly the crutch on which command riggers lean.
Lastly, there ARE good reasons to jump in. The big one is spoof-proofing yourself; sometimes less dice and biofeedback is worth the immunity to spoofing. The second one is using specific non-FA weapons; one of the nice things about gunnery is that it's universal, so you can slap a sniper rifle on a drone and then jump in and snipe people with Gunnery, and 2 shots at a smaller dice pool is better than 1 shot at a bigger one. Also, Mind over Matter is fun for jumping into stuff like buildings that was never meant to be jumped into.