First, I want to congratulate the team that has created this MAGNIFICENT game, one of the best I've played and certainly the best when it comes to WW1. I'm here to give my proverbial two cents on some minor issues and to make few suggestions.
1.) The fleets. The cohesion drop is just ridiculous! I'm baffled by the idea, that a ocean going fleet would lose 70-80-90% of it's combat effectiveness while swimming in a minor sea, during the summer, in a defensive mode, without storms, mines or other things impeding its movement. I don't see a historical or a gameplay reason for this either.
IMO - the cohesion loss should be reduced in order to make the naval game not so forbidding.
2.) Chemical warfare. The NM drop because of CW, IMO, should be discarded. Let me explain. Historically - the use of gas was not so much of an internal issue in the warring societies, but a PR issue on a international level. I think it would be more fitting that the CW use should make the neutral nation lean towards the other side (1% or 2% at most). The NM as of now is depletes rather fast even without resorting to chems.
3.) Movement again. I don't know if would be technically possible, but could you make at least some system that, even vaguelly, predicts how much of a cohesion loss would going from a point A to point B incurr? I was baffled when a rather large army went through a deep forest, during the worst winter ever and the action didn't seem to lower their cohesion one bit! In the mean time - smaller force, went through a clear, railway road / destroyd rails however/ in the same weather and its cohesion dropped like 1/4 to 1/3! Plus, the traffic penalty is great as an option but again - I'm a bit at odds to understand when will it apply - for how much a penalty etc. I know that chance is a large part of war but, nontheless.
4.) I'm not sure if this exist already, but it would be cool if interlinked trenches give some bonus during MTSG. Historically trench networks were very important for the proper supply and the circulation of troops near and on the front.
5.) Artillery duels and raids in no-man's-land. Again, I don't know if this is technically possible at present, but it would be very cool if the entrenched forces, facing each other on the Western Front for example, could engage in shelling WITHOUT actual pitched battles. Something like an option to switch on/off if you think your arty and munitions are superior to the enemy's and you want to chop him a bit. Also, it would've been great if there was an option for low-scale raids, which do not result in major battles, but have the chance to chop a bit of the enemy's cohesion/manpower.
6.) Armored cars. The idea to put armored cars is great, but as of now I don't see them actually doing something in battle. Having, even moderatelly armored car in maneuvre-friendly areas such as the Eastern Front and the Middle East is a force multiplyier to be reconned with. As of now - I haven't seen an armored car doing any harm to the enemy, which is unrealistic in battles of movement. A single, well driven armored car could take out dozens, if not hundreds of enemies, while moving, if not taken out by a lucky arty strike. This would be a great feature, especially on the Eastern front, where speed is essential. It's historical too - Brussilov's offensive for example.
7.) Spies. As of now, the spy is a great unit, but his/hers role could be improved in an interesting way. If, for example, the you place a spy in a major enemy city, the capital for example, it would be very cool if he actually gives you info about the enemy movement, or planned movement, or his present resources, or what is he building as units. It could be even better, if a priori info that you have for the enemy /NM, force comparison, rebel sentiment etc./ must be acquired via espionage and not given "for free" so to speak.
Thank you for reading this, and thank you for making this incredible game!