Ok how about this.
Isolation or Blockade
During collect income phase if a territory is completely surrounded by hostile/neutral territories and/or hostile sea zones, its income cannot be spent in other territories.
That income and only that income can be spent in its IC or VC during purchase units phase this turn.
That income is forfeited if not spent this turn.
eg. USSR holds Karelia S.S.R., Archangel, Russia, Kazakh S.S.R., Caucasus, Ukraine S.S.R., and Belorussia. Germany holds West Russia. Germany may only use West Russia’s income on Western Russia or it is be forteited.
Industrial interruption or Production interruption
During collect income phase if a territory suffered one or more attacks since your last turn and at least 3 combat cycles (excluding dogfighting) has occurred in one or more of these attacks, its income is reduced by 1/4 rounded down to the nearest IPC.
eg. UK attacked Germany’s Western Europe and 3 combat cycles excluding dogfighting has occurred. Germany collects 1 (6 / 4 = 1.5 = 1) less IPCs from Western Europe next turn.