I actually think it could boost the gunner quite a bit if they could load special ammo for themselves and others without having to wait through the animation.
This way a gunner could get an entire ships weaponry ready in moments; freeing up engineers for much more valuable tasks and pitch in a maintenance hand themeslves while running between guns.
Agreed. It's more intuitive that way too. I thought it worked like that for a long time and that it was other gunners or engies dispensing the ammo but... obviously not. Sitting on a gun till that last pip of reload time disappears
just to ensure a specific ammo type is loaded diminishes the role of a gunner because they've got to sit there waiting for a timer when they could be loading other guns, fixing stuff or y'know,
gunning. By allowing unattended reloads you're giving the gunner a lot more to think about and juggle, much like the engineer.
Make standard/vanilla rounds an ammo type so engineers have to choose them or a specialised round (this echoes the gunner's choice of going mallet, wrench, spanner or riskier tools), and allow gunners to reload ammo unattended and I'm convinced you'll see much more diverse and realistically viable crew compositions as well as more interesting (and intuitive) play for gunners.