Eldritch_Lord
Adventurer
As some have mentioned previously, the niche of the casting paladin and ranger is that of the hybrid. There are martial classes that can fill the shoes of either (in 3e, a barbarian, wilderness rogue, scout, etc. for the former and a knight, heavily-armored fighter, crusader, etc. for the latter). There are magical classes that can fill the shoes of either as well (wizard, cleric, or druid for the former depending on which edition's ranger you're using, and cleric or favored soul for the latter). Given a multiclassing system that doesn't suck, you could build a "level X ranger" that is a fighter 1/druid X-1 or fighter X-1/druid or anywhere in between. However, it is the synergy between the two that would make the ranger class worthwhile.
Take the duskblade as an example. It has good BAB and up to 5th level spells, which is something you can achieve as a fighter/wizard. However, it has class features like Quick Cast and Arcane Channeling and an altered spell list and progression (heavy on buffs and touch spells and not much else, plus tons of low-level slots) that let it synergize its casting with its fighting in a way that no permutation of a fighter/wizard can. The late-3e ranger is similar: his list is full of archery- and nature-related spells that are specific to the ranger list, making an archery ranger play much differently from an archery-focused druid or fighter or druid/fighter.
So the ranger can easily find a place in 5e if it is a hybrid that goes beyond the martial/caster multiclass. This could be a full class (that would probably look like a duskblade/arcane archer in terms of schtick), it could be a kit/PrC for multiclass druid/fighters, it could be a mutlciass feat like Swift Hunter et al. that hybridizes two classes, whatever, as long as it does more than "nature-y fighter with spells."
Take the duskblade as an example. It has good BAB and up to 5th level spells, which is something you can achieve as a fighter/wizard. However, it has class features like Quick Cast and Arcane Channeling and an altered spell list and progression (heavy on buffs and touch spells and not much else, plus tons of low-level slots) that let it synergize its casting with its fighting in a way that no permutation of a fighter/wizard can. The late-3e ranger is similar: his list is full of archery- and nature-related spells that are specific to the ranger list, making an archery ranger play much differently from an archery-focused druid or fighter or druid/fighter.
So the ranger can easily find a place in 5e if it is a hybrid that goes beyond the martial/caster multiclass. This could be a full class (that would probably look like a duskblade/arcane archer in terms of schtick), it could be a kit/PrC for multiclass druid/fighters, it could be a mutlciass feat like Swift Hunter et al. that hybridizes two classes, whatever, as long as it does more than "nature-y fighter with spells."