#1 Base Ranger needs to = "Spell Less"
Originally/Traditionally, spell-use for rangers didn't start until 7th or 8th (9th?) level. Subclasses get picked at 3rd. That's enough of a jump up without having them be completely dependent on spell use for all of their shtick.
#2 Tracking & Wilderness Survival. Built into the class as a feature and "better/more effective" than anyone else is capable of doing via a tracking "skill" or feat. Surviving (food/water/shelter, if they are to be had) in wild/"uncivilized" lands should be trivial/a given for any ranger PC.
#3 Favored Terrain. The Ranger story, in nearly all iterations, is that they are warriors of specialized skill in their particular borderlands/wilderness/protecting a given civilization, whatever it happens to be (woodlands [default/most common assumption], dessert, coastal, mountains, "urban", etc...).Their stealth, survival skills, their combat ability (see Favored Enemies, below), extra language(s) they might know, maybe enhanced speed/movement rate through a particular type of wilderness, their nature & historic[or "forgotten"] lore, and heck maybe even stuff like their very AC, are all dependent on their terrain of origin. "Favored Terrain" needs to be a pivotal, if not "defining", feature of the ranger.
#4 Favored Enemies/Hunter's Prey/Ancestral Foes. The Ranger story, in all iterations, is that this specialization extends, specifically, to the most common enemy/threats to their particular civilization/settlements/populated lands. Combat bonuses, to hit and damage, bonus to tracking these creatures, bonus to lore/behaviors of these creatures, all depend on this [again] pivotal if not defining feature.
#5 Enhanced [Rogue level?] Stealth. Whether positted as "thieving" or not, Hiding/Concealment and Moving with Stealth/Silently are a given to a ranger's survival, livelihood and fighting style.
#6 Incidentals/situationals/extended non-combat features. Some of these might be included in the base class, some might be better served ass sub-class distinctive features, that's a matter for a more thorough examination/write up than I have time for now. Or, heck, doesn't fit 5e's format, but you could just list all of these things and say a Ranger gets to pick...I don't know, 2 or 3 of them as they see fit. But I'm talking about things like: Herb Lore/non-magic Healing or at least poison slow/neutralizing; Animal Handling/Empathy/Training [probably better served in a Beastmaster subclass redo); gaining Fighter "fighting style(s)" as they have now; LIMITED/MINOR Druidic Spell Use; Scrying/Clairvoyant Magic Item Use; maybe Scroll Use; LIMITED/MINOR Arcane Spell Use; maybe extra/enhanced "rogue" options for a more "thiefy/bandit/Robin Hood ranger type: trap detecting/setting, lock picking (probably not, but for an urban ranger, i suppose so), agility/climbing, etc...
Sub-classes, then, can be a bit more distinctive.
1. Beastmaster: everyone seems to want but needs a complete (NOT OP'd!) rework, but the animal empathy, maybe a natural speak with animals ability, gain an animal companion (maybe additional as you level up) but continue the "not an automatic extra set of attacks every round for me" thing.
2. Guardian: focus on the "protector of civilization" trope, enhanced combat abilities on Favored Enemy(-mies), maybe gaining/adding more as they level up and/or adding more/extra Favored Terrains as they gain experience in different environments.
3. Slayer: Play up the "Giant/Goblinoid-kille/Monster-Hunter" angle. Combat enhancements for fighting specific creatures and/or a wider array of creatures than the standard/base Favored Enemy(-mies). Maybe a tracking bonus, extra languages, other stuff that is more "the Hunter" sub class they have now, etc...
4. Warden: Druid magic, or any/all magic, Magic Item Use and Arcane Lore built in, more spell-dependent variant.
Throw in a Bounty Hunter Background or Feat and I think you've got all of the bases covered for 5e.
That's about what I've got for a 5e rehash of the ranger. I think it would work. But, if/since you're beginning "from the ground up" SPELL-LESS RANGER BASE. Magic for the ranger is/has always been/should be an "add on/to", not a default.