What products in boat orders that makes you skip that boat?

You could flag the crates for help, or use Tom booster. If you've done free or paid farm pass you should have either boat help or Tom booster.

Since I finished my achievements I never do boats anymore, unless I need puzzle pieces. I don't even do them for farm pass. I skip them and still complete the farm pass season. 

I usually only do boats that I can comfortably fill. I send away all cheese / goat cheese boats, and soy sauce boats, puzzle or not! But that explains why I don’t have all the sanctuary animals. They stay asleep most of the time anyway because it’s hard to keep wheat bundles for them. Plus they give XP, which I don’t need, and only 1 maybe 2 bonus items. I really concentrate on townies because of the bonus items

Wow!  I didn’t know activating a booster while the boat was at the dock would fill crates!  Great tip!  This belongs in the “Things you didn’t know you didn’t know” thread.

For sure flag those cheeses and ask for help! I have tons of cheese and diary and often fill those crates for others.

Make sure to use something like red hats or rustic bouquets so the ad will stay up for a few cycles if needed.

Feathers and lobsters are my sendaways but once in a blue moon (e.g., during an event where I’m loathe to send a boat away) I will ask for help even on those, and I’m always pleased and amazed at those generous farmers who fill those awfully hard things. Never failed to get help on even the worst boats.

I avoid boat orders in general. The rewards are not sufficient in my opinion. My focus is on the town, it's full developed and you have more choices, because you can dispose a townie if his wish seems too brash.

Previous I did boat orders when I had the chance to get 5 expansion permits, but this is long ago. And I think it will never occur again since the farm pass was established.