Tech should capture the most prominent ones:
1. Superstructure
2. Tanks
3. ASW (Anti-Submarine-Warfare) (which is Hydrophones and Depth Charges)
4. Chemical Weapons and Countermeasures (Chloric Gas, Mustard Gas, Gas Masks)
5. Fighters, Bombers
6. Heavy Artillery, Railway (or Longrange) Artillery
1: Later in the war even more extensive defense systems were build. Massive concrete structures significantly improved defense because infantry and light artillery were significantly reduced in their offensive power.
Effect: Attacking Infantry/Artillery -1
2. Tanks were not introduced before 1917. At first they were extremely unreliable getting improved during the war.
Introduce some kind of “reliability” roll to determine which is inactive during a combat. Reliability gets improved with rounds.
Make them cost 4 therefore and to my opinion a tank should negate the “trench” effect for one infantry.
3. ASW was introduced not before 1916 and even then UK had not the proper ship types to to use the technilogy in an effective way.
Submarines should not be able to be detected before ASW is researched. Submarine ruled the seas 1914/1915 almost uncontested.
If researched destroyers get a detection roll and a depth charge roll on 1.
4. Chloric gas was the first gas attack to be used in WWI. It was blown towards the enemy trenches. Mustard gas was used later fired from artillery to eliminate the unpredictability of wind.
Both should be preemptive strikes before combat.
5. All aircraft were reconnaissance planes 1914 with A0/D0 at the outbreak of war just improving artillery accuracy.
3 different steps of fighter research could get the combat values up. Bomber can be researched after you reched step3 of fighter development.
6. Almost all artillery 1914 was light field artillery (except G and A-H)
Heavy Artillery rolls with 2 dice,
Railway Artillery rolls on 3, can shoot from one tt afar and is not affected by superstructure. Cannot support infantry though.