The warden was a really neat Idea in 4e for me. Tougher than a barbarian, flavorful primal attack powers, and some interesting versatility (kind of), a pretty darn solid defender.
Things that would make a warden to me:
-d14 hitdice
-Choices about becoming even tougher, a better protector, or a number of other thematic things
-powers that had a strong primal feel, often area effects that weren't very damaging, but provided good control
-Guardian forms that made big fights feel cooler when you drew upon the strength of a mountain to withstand the punishment of a dragon was certainly going to pour onto you
There are a couple of candidates in 5e:
1) The totem barbarian is very reminiscent of the warden with its totem animal forms and such. You have some level of choice, and can go for toughness, mobility, teamwork, much like wardens could. Probably what I would go for if I were trying to recreate one of my 4e wardens.
2) The vow of ancients paladin is a different version of a woodlands knight, imo. It isn't a replacement for people who liked the flavor of the warden, but could fulfil the desire of someone coming fresh to the concept of forrest knight.
3) ranger or druid: You can make a primal warrior and pretend its a warden using these classes. But I don't think they actually cover enough of the warden feel to make someone who was really into 4e wardens to feel like they've made a warden (that is to say, I wouldn’t buy it).
A 5e class of warden would be pretty cool, but I'm betting that the official feelings are that one of the aboves is enough for us, and I could probably feel like a totem barabarian is close enough to my old warden that I won't lose sleep over it.
Things that would make a warden to me:
-d14 hitdice

-Choices about becoming even tougher, a better protector, or a number of other thematic things
-powers that had a strong primal feel, often area effects that weren't very damaging, but provided good control
-Guardian forms that made big fights feel cooler when you drew upon the strength of a mountain to withstand the punishment of a dragon was certainly going to pour onto you
There are a couple of candidates in 5e:
1) The totem barbarian is very reminiscent of the warden with its totem animal forms and such. You have some level of choice, and can go for toughness, mobility, teamwork, much like wardens could. Probably what I would go for if I were trying to recreate one of my 4e wardens.
2) The vow of ancients paladin is a different version of a woodlands knight, imo. It isn't a replacement for people who liked the flavor of the warden, but could fulfil the desire of someone coming fresh to the concept of forrest knight.
3) ranger or druid: You can make a primal warrior and pretend its a warden using these classes. But I don't think they actually cover enough of the warden feel to make someone who was really into 4e wardens to feel like they've made a warden (that is to say, I wouldn’t buy it).
A 5e class of warden would be pretty cool, but I'm betting that the official feelings are that one of the aboves is enough for us, and I could probably feel like a totem barabarian is close enough to my old warden that I won't lose sleep over it.