If the numbers for Zapp are actually accurate in game, that's a bug. That specific figure only makes sense if it is using the ranged damage table, and no melee AT uses its ranged damage table for anything anymore. (Stalker snipes were the sole exceptions prior to...Issue 13? Or maybe it was 11.)
As for the rest of it...they follow the general guideline that APP/PPP powers have double the recharge and 125% the endurance cost of their primary/secondary equivalents, and evidently Geko decided that interrupt times should follow a similar principle despite there being no other epic powers with interrupt times. I cannot imagine why he thought this would be a good idea, but Geko was so far out of his depth as a powers designer it is frankly a wonder he didn't drown. I cannot guess why Castle has left the interrupt times as they are.
It's also worth noting the PPP snipes show some artifacts of obsolete design. When they were first released in Issue 7, they used the stalker ranged damage table (0.6 modifier) and their damage scale was calibrated so that they dealt identical damage to blaster snipes while hidden (or otherwise scoring a critical hit). Several things have changed since then: snipes were moved to the melee damage table (though it looks like Zapp may have relapsed), the stalker melee mod was changed from 0.9 to 1.0, and the blaster ranged mod increased from 1.0 to 1.125. The net result of these changes is that stalker snipes actually do almost 50% more damage than blaster snipes on a crit, which is not an unreasonable assumption to make.
Alternately, you could view them as 66% of an AS, at 150 foot range.
That six-second interrupt pretty much guarantees they're good for nothing except set mules and party tricks, though.
Also note that You will always shoot while hidden, guaranteeing a crit on every snipe.
Only reason I grab the snipe is for the nice and cheap +7.5 recharge.
Your character does not have capped defense. Depending on your AT the cap is between 175% - 225%. Your defense is not teal in the combat window, it can go higher. STOP SAYING IT IS CAPPED! The correct term is Soft Cap.
I enjoy playing in Mids. I specialize in Melee Characters, other AT's usually bore me.
When comparing sniper attacks to other AT sniper attacks, why is there such a difference in the functionality of it?
Here's a comparison table of sorts, comparing Blaster sniper attacks and Stalker sniper attacks at base values.
Regarding Stalker snipers, there are a few points I want to bring up:
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