Takes a simple barrage to decrew a pak 43 (Assuming there aren't infantry near it, so it's pretty much lost.) Takes lots of barrages to destroy 17 pounder. It shouldn't be a problem considering you'd get anvil engineers to repair it once the barrages stop. And if you're still having problems with artillery, try placing it further back, and (or) pushing to destroy the Artillery instead of turtling.
Lol, you obviously don't play with UKF. What is a simple barrage? 150 muni? requires vision? if it's flame, it'll be recrewed. artillery isn't instataneous and there's no guarantee it will hit and destroy. or are you talking about 250 muni abilities? or are you talking about mortars that require more lose range?
the 17 pounder will get barraged non stop. JT can attack ground until it is destroyed. All indirect fire can attack ground until it is destroyed. leig outranges everything but heavy arty and mortar pit. your miracle engineers will die repairing it. put it? put it where? it's so large to begin with. again, i'd trade a 17 pounder for a pak43 anyday. if you're okay with that, i'll know it's balanced. If that ever happened, i'd hear Axis crying for changes.