I don't know if anyone is still reading this or if I should post in suggestions, but:
SPA's need to be adjusted to not destroy spawns. Commander arty was adjusted the same way after release and is in a good state. SPA's are a strong alternative to static arty (and personally, I would rather SPA be the only arty, rather than static arty), but the potential for spawn destruction can become unbalanced.
Comp rulesets (please don't flame, not just a comp suggestion) have considered banning static arty in favor of implementing SPA's, but testing has shown SPA's potential to wipe outposts is too strong to move forward with such a change at the moment.

