IMHO, it would be more realistic and more... enjoyable if a compromise between the two sides was used (static income reduction vs. purely reactive income reduction)

a base static reduction (the "union workers") would remain the same when at one research level (maybe the ability to lower the level at a cost) but there would also be a reactive variable (food/air/water/repairs/materialsf for repairs/ammo) that is added on top of the static cost.  i.e.:

lvl 1 research: 0+(x (fleet supply points used) *.25%)

lvl2 research: 4%+(x*.3%)

lvl3: 8%+(x*.5%)

and so on (obviously going to need some fine tuning)

this would help losing players make a come back and rebuild their fleet after it's been destroyed, giving them a chance to halt the now unopposed fleet annihilating their planets.  once the tide has turned one way, it doesn't really turn back, using the cost-reduction system currently in effect.