I most certainly am willing to embrace the idea that MP vs SP balancing idea group should be different.
The only real question left is how?
I don't know, this is for PDX to find out. I wouldand will gladly help in any way I can, but I can't change values and test on a large scale.
Because they ARE useful in MP. Well naval is. Even limited in scope, what point does removing the group actually do? Just leave it as is until it can be worked on (or the stuff attached to it that is kinda bokred). If its a false choice... well it kinda isnt. Naval is a great example... it does EVERYTHING it does VERY well.... its just that in SP its not needed.... unless you want it, because flavour. Is it an optimal pick... well no, and in the end that's fine too. Whenever the naval AI gets some help naval COULD be better for some nations but probably just better for the nations its already geared toward.
IMO this game will NEVER be 100% balanced because its not supposed to be. This isnt competitive starcraft. That and many players choose non mass conquering/optimized builds because they are having fun (I do both, WCs and just playing for stupid goals/rp reasons). Sandbox games are like that. Naval and maritime fall into this perfectly (so does expansion but hey, that group does need some help though). The problem in the logic is espionage... which will now sorta fall in that category but it really isnt "espionage" in that case with -liberty desire and - corruption, but hybrid trees are also like that (aristo/pluto, espionage, influence, expansion). I kinda like the idea of the age ability to form chain claims on the end of the espianage group, that would be cool.
Now if something is totally out of whack (which IMO only humanist falls into as it should be VERY powerful in Dharma) it should be brought down a bit or modified, or other picks brought up, but they cant just bring up the rest of the groups to humanist level, there is enough power creep already.
Finnaly MP vs SP doesnt have to be balanced separately, different groups will have higher priorities in one vs the other because they play very differently. Especially competitive - but it is true with coop as well, and in the end accomplishes the same thing. Asymmetrical starts and real world diplo will have larger effects then most idea groups... unless Prussia or equivalent with all necessary ideas..... but then its the other players fault. Or if players can not coordinate properly, but again thats in play not "ideas". In the end MP isnt just Dev clash style MP, you can play even that many different ways and none of them are "right", so we need one rule set that applies properly for the game mechanics, not meta mechanics.
I need to stop wall of text.....
Like I said, removing them is a possibility. I am not saying Naval should be removed, but just consider that chopping up Naval ideas into two might work.
Maritime:
1: Add +100% prestige +50% navy tradition from battles
2:
3:
4: Add -33% morale hit when losing a ship
5:
6:
7: Add +10% global engagement width
Fin:
Logistics
1: +5% global movement speed
2: +1 attrition for enemies -5% hostile movement speed in friendly terrain
3: -10% ship building time
4: +25% looting speed
5: +1 Leader without upkeep
6: +25% galley combat ability +20% heavy combat ability
7: +10% naval forcelimit +10% land forcelimit
Fin: +10% ship durability
This way you can choose for a superior naval force whilst not sacrificing your entire idea group. The 10% ship durability, +10% naval forcelimit and +20% heavy combat ability should more or less secure you a superior navy. I mean the current Naval ideas goes 100% naval combat focus, whilst you will only need a 50% edge.
Please note that I pulled these numbers out of my behind and it is more to give you an idea of what I mean by removing naval ideas.