Seems like it should cost 375 instead of 325 power
Since it is basically an artillery piece with high damage, it more than warrants that cost imo
SM/Ork tanks should be adjusted too...(SM Preds are not good and Big Trakks spammed can be quite a nightmare to fight since they can murder everything with AoE arty fire).
Basically, units with long range and high damage need to be nerfed in some way to prevent them from being too easily critical mass'd and just roflstomp any unit comp they see