When this helps:
1. The target is stationary. Usually in the open and simply needing a lesson in cover. Why must I miss when my target is a complete fool, and I’m dialed in???

When this doesn’t help:
1. Any time the target is moving. (no benefit for leading shots at moving targets)
2. Or the target is in cover.
3. or WHEN THE TARGET IS NOT SEEN. (get it? no benefit for blind shots)

(Because I’m smarter than most all of you, that’s why) :D

Second, 15-20 second aim time would be redicilous. Take the ARL V39. It has a very limited turret/barrel traverse and it takes so long to turn and start the aiming cycle again. Now there are SPG’s who also have very limited traverse. for these machines it would be impossible to have time to aim effectivly before the tanks have already moved.

When it comes to splash damage: spalling and other forms of trauma from the shock of a nearby HE blast certainly was a thing, although WoT probably does exaggerate it somewhat. OTOH, historically there were few artillery SPGs used in action with calibers over 155mm: in my experience the effect of splash from 150mm calibers is usually fairly trivial unless the target is really lightly armoured, so the only high-tier artillery that really behaves as we would intuitively expect artillery to behave is the French.

That said, mechanically speaking, the distinction between arty and other vehicles is the artillery fire mode instead of sniper mode, which gives them two things:

* The ability to fire, with any reasonable degree of accuracy whatsoever, at targets outside of their draw distance.

* The ability to use high-arc weapons to fire over obstacles. (Some other vehicles can do this, but it’s usually a PITA to aim at an enemy tank across a ridge or something than at the ridge itself, and you can never use sniper mode to do so.)

Arty, however, pays a lot for these abilities: compare the SU-152 (historically a close-ish support artillery SPG that was often used as a tank destroyer because it proved effective at that role) to any arty piece with a similar gun: the SU-152 has better aim time, accuracy, and ROF, even if you’d think the often open-topped arty pieces would have an easier time with the reloading at least. The current game parameters are essentially a compromise between what such an SPG could achieve with direct fire and the expectations of artillery performance with indirect fire, giving arty arbitrarily longer load times and reduced accuracy in direct fire (although that could be excused through the arty SPG lacking rangefinders and other targeting optics to assist with aiming).

Thus, I would probably be inclined towards breaking that compromise and explicitly seperating direct and indirect fire:

Arty is given two different sets of accuracy and aim time parameters. The first is ‘direct fire mode’ – this applies when the SPG is within draw distance of the target location and has a direct line of sight towards the target. Essentially, anything that a tank of another class would be able to shoot at from the SPG’s position. When firing in direct fire mode, the SPG has similar aim time and accuracy to a TD with an equivalent gun: however, any arty firing in this manner is, essentially, behaving as a TD with all the attendant risks.

The second is ‘indirect fire mode’, which could be represented by the shell arc line turning yellow (as opposed to green, which would be for direct fire, and red, for a blocked line of fire). In this mode, the arty has much lower accuracy and much greater aim time: this represents that instead of the crew being able to sight the target themselves, they’re relying purely on coordinates provided by their allies in order to line up the target, making things much more complicated and introducing further margins for error. Employed in this fashion, the arty piece becomes area denial: the chance of any particular shell landing dead on target is slim; however, it the target remains in place than enough shots fired will lead to damage, and a higher concentration of enemy tanks will lead to a higher chance of each shell doing some damage.

In either case, reload times will also be buffed to something comparable to a TD with an equivalent-sized gun, allowing them to act more like a TD when in direct fire mode, and making the more frequent misses less painful when in indirect fire mode. (Economic adjustments may be necessary to adjust for the greater number of missed shots, but then again, arty does continue being a relative moneymaker longer than mediums and heavies do, so this may simply bring them back more into line.)

They kill more medium and light tanks than TDs!
They need a delay to stop it, when you receive a position by radio, you don’t receive it instantly, you don’t receive the name of the tank, the position, the turret possition and the map obstacles instantly, they need time to give you all those informations, in wot you receive it instantly, that’s why arty are so dangerous to medium and light tanks in wot, this is the main change we want to see.