-Its price is its counter, you can field 2 squads with that much mp, use that to your advantage.
-If he has the luxury of keeping his arty until you retreat, then you're not pressuring adequately.
-If you are getting a hard time against (this) arty, hold off your commander pick until you see what your opponent picked, so you can counter-pick. It might be 'annoying' to not be able to 'play what you want any time you want' but this is a pvp game, it's not scripted.
I don't generally base rush to see what base structures my opponent has and most of the time the first salvo is enough to take out a considerable amount of my units.
I don't mind constructive criticism but I'm not an idiot. I know it's pvp. I was just bringing up the point that base arty that can fire on your base seems a bit ridiculous.