I find it hard to reconcile the F rating on Interest Groups vis-a-vis the A rating on CC's Endorse Political Campaign. Interest Groups usually results in removing 3 opposing cubes and replacing them with 3 of your own - that's probably roughly the same value as adding 4.5-5 cubes or so. Sure, the 6 for Endorse Political Campaign is better, but with the cost of 15 Vardis it balances out. I'd rate Interest Groups a solid B, maybe B+.
I agree with TboneG on Buy Private Island. It only makes sense if you're in round 5 and you're not going to be able to raise your maximum capital marker (or maybe only one space), or perhaps as a tax dodge if it gets you underneath an expensive tax bracket boundary (but you'll want to be sure somebody won't screw you by buying more food than expected - I always try to watch what the tax effects of buying an unexpected food from CC instead of the foreign market might be, even if it's not the cheapest option). Early, that's money you're not using to expand your business to score points later. I'd rate it a D. Maybe a D+ in a 2-3 player game, since paying the state is less of a downside when nobody is playing them.
I agree with TboneG on Buy Private Island. It only makes sense if you're in round 5 and you're not going to be able to raise your maximum capital marker (or maybe only one space), or perhaps as a tax dodge if it gets you underneath an expensive tax bracket boundary (but you'll want to be sure somebody won't screw you by buying more food than expected - I always try to watch what the tax effects of buying an unexpected food from CC instead of the foreign market might be, even if it's not the cheapest option). Early, that's money you're not using to expand your business to score points later. I'd rate it a D. Maybe a D+ in a 2-3 player game, since paying the state is less of a downside when nobody is playing them.