Interesting, I've had no such issues so far. The few batches I've made, I loosely followed the recipe but mostly eyeballed the amount, and it's always come out tasty. I've yet to try this round, though
Phlogiston
Something like this would probably be my go-to: https://www.amazon.com/Golf-Ball-Retriever-/b?node=3411041
Any area I've cached, there have always been plently of caches that don't require a TOTT -- so no, you don't need one, but it might come in handy, depending on what you want to find.
Around where I live, probably the most common TOTT is a long pole to get caches down from trees. Don't exchange this for a ladder -- a lot of the caches are up in thin spindly trees growing on uneven ground. They're designed for you to get them with a pole, with both feet on the ground. You can buy golf ball retrievers for not too much money at a sporting goods store, these usually work well.
Other TOTTs I've seen are batteries for gadget caches or a UV flashlight. If you read the cache page, you should be able to get a sense of what you need. But every so often, a cache owner will get creative and make you use something you've never thought of before ;)
Had to check it out on Google Play: https://play.google.com/store/apps/details?id=de.westnordost.streetcomplete
That looks pretty cool! Love that you can play it like a game as a team. I need to try this out
In a hollow stump. Not actially buried