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
The exile clause is the most important part about this card, which is super useful for getting rid of cards like Memory Deluge, Squee, Dubious Monarch permanently
It wont go in every deck, but itll be easier to execute than Angel of Destiny if you build it right
When mixed with a card like Deadly Dispute (which Ichor Wellspring is the main target to sacrifice for Deadly Dispute's effect), you get to draw multiple cards to get a nice refresh of your hand while ramping
For one thing, life advantage doesnt translate well into other aspects of the game, such as having more cards in hand than your opponent or having better creatures on the battlefield