Well in your case I could suggest to just tweak the A.I.'s potency yourself. Sure, it's not the most elegant fix, but for the time being you can just alter the values in the XML files for Hard A.I. which should be a cinch.
Extract the .XML files from the PR archives and the file in particular to edit would be "DIFFICULTYADJUSTMENTS". For example under "<Difficulty_Adjustment Name="Hard_Default">" find the "<Credit_Multiplier>" line. If you set it to 2.0 you'll double the income for hard A.I (I think PR default is 1.33 thus 33% higher). You can also set the build time multipliers to a lower value. However just a bit higher percentage wise could already make all the difference so I advise not to change it too drastically.
You'll at the very least be swarmed with lots more units (I know it does not improve their tactics in any way, but I wouldn't have a clue how to do that).
EDIT: Oh forgot to add this: If you plan to implement this take note that it will probably also degrade performance since there will be even more units for the A.I. to manage.
I can't even find "DifficultyAdjustments.xml" in pr. found it in other mods, but in pr... nothing.
if you can find it, can you either tell me how to do it, or could you give me the full difficulty settings for pr? then I should be able to do this myself.