Stamina seems to last the same time for each class so I think Muse wants to keep it the same between classes. Currently using full stamina reduces a reload by 1.6 seconds. Changing stamina duration would sure help, but without changing it the best option is to make the reload bonus more potent. For example 50% compared to 25%- allowing a max reduction of 3.2 seconds of reload.
You're doing the maths wrong. Stamina increases your reload SPEED, not TIME. so it wouldn't decrease the reload time by 0.25 of the stamina usage time. So, on different guns it would have a different effect. A mine launcher will be 3.2 seconds instead of 4, with Gatling it would be 4 seconds instead of 5 seconds reload, with Hwacha it would be 12.5 seconds of reload instead of 14 seconds. Or to take the extreme, a flare would be 18.38 instead of 20.
So you get anywhere between a 0.8 and 1.5 seconds of decrease in reload time, depending on the gun.
You take the reload time, if its lower or equal to the stamina usage time, you can use it throughout the entire the clip so it simplifies the calculation:
reload_time = 1 / ( 1.25*reload_speed )
When you can't use the stamina throughout the entire reload:
reload_time = stamina_usage_time + ( 1 / ( 1 - ( ( 1.25*reload_speed )*stamina_usage_time ) ) )
Also, from my tests I got some numbers concerning stamina, which will hopefully go on the article for stamina once I finish writing it for the wiki so might as well share since it could be relevant to the discussion:
*most of the values were done with a stopwatch and not with frame counting since I was happy enough with the results to not justify the pure waste of time frame counting is:
Non-natural regeneration of stamina:
-When an enemy ship dies, all crew members receive +33% of their stamina bar.
-When an engineer rebuilds a component he receives +30% of their stamina bar.
-When a gunner destroys a component he receives +8.33%(1/12) of their stamina bar.
(Pilots do not have a way of regenerating stamina other than natural regeneration of time except for the kill ship boost that all other classes already posses.)
Stamina usage durations:
-Engineers can use 3 seconds of stamina.
-Gunners can use 6.5 seconds of stamina.
-Pilots can use 4 seconds of stamina.
Stamina natural regeneration:
To fully regenerate a stamina bar:
-Engineers will have to wait 50 seconds.
-Gunners will have to wait 60 seconds.
-Pilots will have to wait 50 seconds.
Wait time to usage time ratios:
-Engineers wait 16 2/3 seconds for every 1 second of usage.
-Gunners wait 9.23 seconds for every 1 seconds of usage.
-Pilots wait 12.5 seconds for every 1 seconds of usage.
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I like those numbers quite a bit for the next reasons:
-Pilot stamina is the most scarce due to no abnormal regeneration - It's an emergency tool.
-Engineers really do only need stamina more when things go down, so you can rebuild the components that go down in danger to gain a bit more stamina to survive more. +30% helps a lot in those situations from each rebuild, only complaint I have is that 3 seconds seem too low of a number for a more substantial usage - because lets face it, faster moving is not helpful in most situations and when it is, you run out too quickly.
-Gunners stamina is on a good number usage time wise, with low regeneration for every component destroyed - its good because it accounts for the large amount of components destroyed by hwacha.
As for normal regeneration:
-Engineers and pilots both have a lower regeneration time than the gunners. Pilots have a lower regeneration time because of no other regeneration means, so that is good. Engineer stamina will have lower regeneration time than the gunners because he will not be getting any stamina during only repairs and not rebuilds, while the gunner will be constantly getting components destroyed from the beginning of the engagement.
-Which brings us to gunners, they don't need high regeneration since from the beginning of the engagement, where they actually need the stamina, they will be partially getting it from components destroyed so it justifies low regeneration rate.
-As to +33% to all crew members, in most cases I don't see it help a lot, since you have already killed your enemy and by the time you get to the second one you already regenerated about a third of your stamina or more. But I guess its a nice way to give a positive boost to every crew member after a successful kill, and, in addition, provide for a way of faster pilot stamina regeneration.
My only conclusion is that stamina, duration-wise, normal regeneration and abnormal regeneration all seem to be pretty well balanced with the exception of the engineer's low usage duration - which I would like to be increased to 4-4.5 from 3, with regeneration rates not affected.