Lord E, i've just checked out your AAR for the first time and I've got a couple of questions/ suggestions (I've recently finished a game as Denmark, which faces similar Baltic political issues)
Are you still Catholic? You should be Protestant by now. Convert, recover your stablity, then get some colonists (not Traders) to North American Tobacco or Fur provinces. If you can build a couple of cities by 1550-1560 you can use the extra income to turn you attention back to the Baltic in late 1500s.
Are Riga and Danzig still controlled by Pol-Lith? Check the province incomes. These provinces have CoTs so they are lucrative. It's probably worth a war/ raising loans for troops to get these. Wait until Pol-Lith is in a war, then join the feeding frenzy. Don't forget to take the capital, it's close to Pol-Lith's northern border, then you'll have a major advantage in any peace negotiation.
You say you are in an alliance with Port/Pomm etc. Pomm is useful for now, as you can use their provinces as a highway into Pol-Lith, but I think you'd be better off with a defensive alliance vs Denmark. Sweden (which is either Protestant or will be going Protestant soon) is your obvious partner.
Can you give a list of your current provinces, army strength etc?