What's the best fighting game currently?

Hey folks,

I am super interested to buy a fighting game recently...with the release of Tekken 7 and Injustice 2 - there are some really decent fighting games on the market.

I'm currently deciding between Injustice, Tekken or Street Fighter V...

Could you help me what to buy?

I would love to play every character once I buy the standalone version! Is every character unlocked in those games? I heard you have to buy certain DLC packages for Injustice....

And is there like an ingame lootbox system, where your gear boosts your character stats? (I hate those...makes me feel that I need more money than skill to get into high ranking...) Or is every fighter equal in terms of character stats?

I would love some insights about the games! Would really help my choice between those!

Cheers!