So I will make it short , it is very hard time for builders without Sunderer being able to drive in your base ,park there, give infinite respawns to everyone who wants to just spawn on your face. Idk why there is no non-deployment area just as with outposts, what is the point of the base if enemy can just drive into its core an set up spawn point.
Another point I want to add, builder bases were never meant to be squad effort, game is to fast paced for squads to care and take time besides very rare occasions. Bases are meant to hold off offense, or give some standing point by people who are willing to put in time and effort to construct them, now you just get rolled by single Sunder .
I ultimately disagree here. It's been a tactic since the dawn of time and I believe it should remain so, both helping attackers and yourself, your own sunderer, being deployed in your base. The recent sunderer update has also offered builders another utility to further defend themselves. If you build correctly, a sunderer shouldn't have an easy way into your base first and foremost. Secondly, you must defend your vehicle pad. There are utilities to help you do that, and even if an enemy does pull a vehicle from your pad, nothing is stopping you from doing the same. I believe base building solo in the current system is certainly tougher but not impossible. Having multiple players does help, but still success can be found doing it solo. Reading the map and anticipating where the war moves may also offer some insight to get ahead of that 'fast paced' strategy that is planeside 2.
You're right, we need NDZ within Silo's radius or 75% of its radius. It is also necessary that transport terminals are not hacked.
Your logic can only apply to old construction, NOT new. The old construction had very simple block shapes allowing for simple assembly, a single spawn coming from fragile spawn tube. The spawn tube is what somewhat forced you to complete your base to its fullest extent. Wall it off entirely with no gaps, minimal entrances, at best 1, you also had structure shield module, AI module for turrets. So, as an example the anti-infantry turret coupled with AI module would protect your Vehicle Terminal from getting hacked (pain spire nor spitfire could accomplish this, not enough DPS), could also cause trouble for enemy infantry trying to enter your base from one entrance, structure shield module would allow you to fire at vehicles from complete safety behind your walls, I personally had a shielded Pillbox directly inside my base in case of a breach. But obviously the Spawn Tube was so easy to destroy with infiltrator or Light Assault, a single infantry could easily disable your entire base in a blink of an eye that took 20 minutes to complete, and the ultimate solution by the dev team was to make to make the spawn an actual building.... But the new structures lack the shape and are oversized, and on top of it, there is nothing to wall off anymore.... It's just not possible anymore, neither Rebirthing or Command Center, too large.... The idea of this new update was to no longer make the user waste time completing the entire design, but rather use simply key structures. Completing a full design would make no sense especially with new modules which double the time to construct your base as opposed to prior.... So you are not meant to wall off your base anymore. I am not playing construction nowadays or this game, but I can imagine the issue of Sunderers, pretty much rolling into your base and spawn camping you coming from Rebirthing Center, cannot pull vehicle from terminal, and neither have any ways of firing back, as you lack the structure shield module and firing positions of old structure designs, which BTW I don't understand why couldn't the developers make Pillbox the rebirthing Center with shielded gates and a spawn inside. The developers didn't think this through at all. Minimal brain power engaged. Ultimately, I noticed since the start after playing for a while, that the only useable structure is Command Center (as opposed to attempting old designs with Rebirthing Center, as the vehicle terminal cannot be defended from hacking attempts anymore and Rebirthing Center can be as well quickly destroyed by vehicles without you noticing as it sticks out, which if it does, you cannot reconstruct it anymore as it won't fit inside your base), but the Command Center is extremely oversized and falls too quickly, which I predicted in 1 second while reviewing it on test server before it even came to live. But it's the only usable structure which simply requires a Silo and anything else would be a waste of time.