Look my good chap what i propose is an easier method to solve the problem using the historical paradigm consider:
DEVELOP ADVANCED WEAPONS
Each country may elect to spend a one-time research fee of ten IP for each available advanced weapon. The weapon then becomes available to buy on that players following turn. Weapons that become available on a specific turn can immediately become available to purchase.
Rail Gun: (Germany only) can conduct a special form of attack on ground units within a range of one territory. They can support friendly units that are attacking and adjacent to the location of the Rail Gun firing twice at eight. Rail Gun attacks are preemptive so the defending units do not get to fire back. IF enemy units attack a Rail Gun it defends at one roll only six. Rail Guns can only move only within connected land territories (not across oceans) by way of non-combat or strategic redeployment (cost 1 SR point).
Katyusha Rockets: (Russia only)
Operates more like artillery and has a devastating preemptive attack. All hits from these units during each combat round are removed from play before the defender has a chance to roll for defense. (Note: they do not aid the attack or defense of infantry units).
Jet Fighters: (Germany turn 10, U.K. turn 12, USA and Japan on turn 13)
Jet fighters cost 16 IP each. Jet fighters defend on rolls of 10 or less, and have a movement of 4. They can evade any Air interception. Anti- Air ground attacks from defending artillery have no effect on these units. They cannot carry paratroopers.
Jet Bombers: (Germany only turn 12)
Cannot carry paratroopers but can evade any Air interception. Anti- Air ground attacks from defending artillery have no effect on these units.
Heavy Bombers
(U.S.A and U.K. only)
Heavy bombers cost 28 IP each. Heavy bombers attack twice on two rolls of 10 or less and can
carry up to two Light or Regular Infantry as paratroopers or air transport. They also move 10 spaces. They defend against air units at 4.
V-2 Rockets: (Germany turn 10)
V-2 Rocket launchers cost 8 IP each. They do not provide anti-aircraft defense. Instead, they may launch rocket attacks against enemy Industrial Complexes. They may only move by rail and have a range of four. Each V-2 launcher may launch one rocket attack each turn. Multiple rocket launchers may occupy the same territory and may attack the same target. Hits are scored in the following manner: 1-2= no damage, 3-4 =1 IP, 5-6= 2 IP, 7-8 = 3 IP, 9-10 = 4 IP, 11-12 = 5 IP lost. When you perform Rocket attacks you take of the money from the nations log sheet, so when they count the economic basis for determining how much money they get it is accounted from their IP levels. Captured V-2 sites are removed from play and cannot be used by other players.
Super U-Boats: (Type XXI class U-Boats)
(Germany turn 12)
Super submarines cost 10 IP each. A super submarine attacks and defends on a die roll of 6 or less and moves at 5. Destroyers or Escorts cannot negate their first shot capabilities. No naval or air unit can directly attack a Super Sub and can only defend against attacks from these units. They are not affected by Destroyers or Escorts and always have a surprise first shot.
Forget about the specifics just notice that on a certain turn “the tech is available by investing IPC by that turn” How simple do you need it? YOU SPEND X ON TURN Y AND GET Z…. good grief this is not rocket science!