That first situation seems like an easy fold. The only hand you can get to win is probably a runner runner straight, so the (1:6) odds don’t nearly justify a call. That silly 1XBB is another round of cards you can play with and your opponents can’t play with. This situation doesn’t seem like a gray area, rather a clear cut fold.

For the second situation, the pot odds for your 4 outs is 16.5%, so if you are in the first position after the bet, your odds are .50/4.00 12% - good enough, not what I would call fabulous. If you are in last position, your odds increase to .50/5.50 9% assuming everyone stays in and doesn’t raise. But the big problem is that there’s a potential flush on the board and you could be drawing dead. Or, if someone has so much as a flush draw (one diamond), their pot odds are at 35% and dominate your straight draw. My choice would be to fold and not try to draw with the second best hand. You might be able to call if you don’t think anyone has you beat now and see what the flop and river brings. For raising to be the right play, you’d have to bet more than 35% of the pot $1.40 in first position or $1.93 in last position assuming no one has already made their flush.

Your third situation is too ambiguous. Is the flop all overcards, flush possibilities, straight possibilities? A small pocket pair is not usually a good hand unless you make your set and the odds of getting it after the flop are 8.4% and not “as good as they ever get”.

Good luck. I hope that helps.