Broadly, there are two types of counterspells in Magic: hard and soft. Hard counters stop spells in their tracks without any restrictions, while soft spells either only stop the spell temporarily, or have an option to bypass the counter
I'm not sure we've quite gotten to the bottom yet on Bloomburrow singles, but in most cases, it'll be better to buy singles you need now as compared to when cards first came out
(2019-07-12) If Bag of Holding leaves the battlefield, the items it contained are exiled forever (and, perhaps, scattered throughout the Astral Plane)
Yahenni, Undying Partisan
At 1 mana, you cant get much better value for a hard counter, and stopping that specific noncreature spell from resolving is often way more important than the two extra mana theyll have on the following turn
(Gatherer rulings contradict the CR fairly often, more so than official rulings in other locations