how to change mod for ship sizes

Don't be mislead by absolute size in kT. The bigger ships are actually proportionally larger than smaller ships in the Balance Mod. For example, in stock, a Battleship hull is only 270% larger than a Frigate, while in the Balance Mod it's 333% larger. A Cruiser is 250% larger in the Balance Mod than the Frigate, while only 210% larger in stock.

I should note though that the Dreadnought did get a boost in size for the v1.15 update, coming out shortly.

Space Empires Depot | SE:V Balance Mod

excuse me, but i can't see formidable difference between 270% and 333%... 250% and 210%

in comparison with full size:

(333-270)/333=0.19 and (250-210)/250=0.16

just 19% and 16% of difference between stock and balance
am i wrong?

And did you count that in BM bigger ships need more engines?

Stock SEV does not encourage the use of multiple ship sizes any more than BM does... There are still optimal vehicle hulls at every tech level.

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Here's an exhaustive thread on ship sizes in the Balance Mod:
http://home.spaceempires.net/ftopict-4368.html

Larger ships in the mod dedicate less space to required systems and can use bigger mounts, which gives them a better dmg/kT ratio than small ships.

Space Empires Depot | SE:V Balance Mod

Yeah, stock is even worse with it's level 10 frigates with large mounts...

P.S.: Though I like the concept, but the research cost should be a lot more expensive - you should have to really invest into it if you want to reap the rewards of large mounts on frigates...

You need to read further into the thread than the first couple of pages. The general conclusion was that all ship sizes were useful and could have fulfilling roles.

Yes, you can change the ship sizes to some degree assuming you don't mess around with engine/crew/life support requirements.

The multi-tracking ability is not activated in SE5.

Space Empires Depot | SE:V Balance Mod

Wasn't this topic done to death already anyway?

Yes, and Kwok posted a link to it.

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So basically, you aren't interested so much in all ship sizes having fulfilling roles, so much as stock's bad formulas that provide way too much hull size overlap?

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In that original game you praise so much there is no need to build many ships besides fighters.

But to get to your original question. Yes, it is possible. You'll have to have a look at a file named VehicleSizes.txt in your Balance Mod folder inside the GameTypes folder of your SEV installation.

plasticpanzers, I think you might prefer Unnamed's Upgraded AI Mod. It doesn't change the tech tree at all, AFAIK.

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"Good morning, Pooh Bear," said Eeyore gloomily. "If it /is/ a good morning," he said. "Which I doubt," said he.

I think what you really want is not the stock hull sizes, but rather QNP. This is how you get a real choice between "fast battlecruisers" and "armored cruisers." BM has its engine requirements set to be proportional to hull size, but it still caps them to create artificial speed limits. Try going into BM's VehicleSizes.txt and removing all requirements that use the function:

Get_Design_Ability_Component_Count("Movement Standard")

(Do not actually do this in the stock setup, unless you also change the Engines Per Move values to be proportional to hull size and modify the engines to provide only Movement Standard ability in increasing amounts. Refer to the values used in BM to get an idea of what to do.)

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You should really look into a true QNP setup..

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Hey, here's another idea for propulsion... someone's probably thought of it before, but I thought I'd post it just in case...

It's sort of a hybrid between full-fledged QNP and the old "big ships are slow" system... basically, remove all engine limits, but set engines per move to be MORE than proportional to hull size! That is, if a 250kT frigate requires 50 "thrust points" to move 1 hex per turn or something, then a 500kT cruiser would require MORE than 100 - say, 125 or something.

That way, you can still make ships as fast as you like (well, within the hull's physical capacity for engines ), but you get diminishing returns on your tonnage investment as your ships grow larger, so you have an INCENTIVE to make large ships slower but you're not FORCED to! (A speed 12 baseship with only ion engines? No problem, you'll just need a LOT of engines! )

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The power of the ancients is now yours to command. You are truly the Master... of the obvious

In BM, while the tonnage of baseships is only double that of a cruiser, in stock (and all mods)the combat icon is at least 20x as big. While it looks impressive on the screen and makes tactical combat very difficult, they still die fairly easily. Does anybody understand why a baseship looks bigger than a tiny planet?
The battle formations are almost worthless with baseships because the spacing is smaller than the silly icons. I usually just get a lump of ships when there are more than 9 in a fleet.

I made a bunch of adjustments to the combat sizes of ships in the Balance Mod for v1.15. I also reconfigured all the acceleration and turning rates, so combat goes a whole lot smoother.

Space Empires Depot | SE:V Balance Mod

Cool!! That's makes me want to try it out right away.