This is a tough one, because you don't want to write just out of frustration if you're anti-arty, but at the same time you need to remember how frustrating it is to be on the receiving end of it.
I've never been a mortar guy/on arty/commander so I don't know how hard or easy it is to be effective, but there are times where I quit in the middle of a map because there is just no fun left in it. The problem we have here is that the usual response ('Well, go spawn at a flag that isn't being arty'd') is a legitimate one, but at the same time, not spawning at Navy HQ on Brest because of it just being mortared to shit all round is very different from telling someone not to spawn there because the Panzer IV's got it covered, or a good German squad is about to lock it down and we need to regroup. Mortars and arty are no less legitimate ways of fighting than anything else, but they aren't enemies that can be fought. You can't send a squad to deal with an enemy mortar battery in the way you can send one to take out a tank, or wipe out another squad.
When I first got to play FH2, after many years of FH1, I expected mortars to be just a little more than background noise. That I'd be attacking a town with my team, and a few guys in another field would be mortared here and there, and occasionally a mortar would get me. That there'd be lucky rounds where I never got it, and unlucky ones where I got it four or five times. In reality, the average infantryman is mortared very, very often on most maps, and indeed on maps like Brest, is often nothing but mortared. Mortars don't need to be less powerful, but I think they should be less often. Whether this is done through removing ammo kits from mains, limiting some respawn time, or whatever, I don't think mortars should be a constant threat. Whether they were in real life or not doesn't matter to anyone who spends half the round staring at the respawn screen. If you hear mortars going off, I think it would be much more enjoyable to think 'Sit tight for a few minutes, and then the coast is clear for a little while until they get more ammo'.
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A slightly related note: I can't miss the opportunity to express my wishes that mortars be removed from 16-sized maps. No one ever agrees with me on this but I will be a very happy guy if these get the boot in some future patch, and if they do, good riddance.