When I added the revised ranger playtest to my game, two players immediately dipped. Which, I think says something about the ranger at level 1-3.
Looking at the PHB ranger, it really is unappealing at first level. Fighters get Second Wind and a Fighting Style, barbarians get Rage, rogues get Sneak Attack, paladins get nothing offensive but can heal, and rangers... Like the paladin, the rangers offence comes later, as both get Fighting Style at level 2. But while the paladin gets smite, the ranger gets... nothing. Favoured Enemy is an out-of-combat power, as is Natural Explorer, and they get no boost at second level. It's a harsh few couple levels.
But when you give it advantage to initiative and advantage on creatures that haven't acted yet, that's a solid bump for a class.
The beast master... that does need a little tweak.
The problem comes down to hit points: damage increased by 5 points per CR as does a wizard's hp with a Con of 12. At 4 hp per level, the beast is squishier than a wizard. And as it's Hit Dice are static, it cannot heal and is a drain on party resources. The fix: the beast gains an additional Hit Dice for each ranger level beyond 3 its master has. Then make it automatically stabilise when it drops to 0 and you're golden.