Ok, I've thought about it a little more. Here's my full assessment:
Avengers: This is OP. +5 to saves is amazing on it's own. There is a +6 saves Legendary cloak that does nothing else. I think either the saves or the extra LoH needs to be removed, minimum. So it has 0.5 average damage less than the other 1H legendary sword as a downside. And it has as upsides: An UR neck (Guarding), an UR head (Crown of Expertise), between a relic and legendary cloak (Pharicus), and almost an additional UR head (Crown of Expertise again, almost: 10 LoH uses). AND THEN IT CAN AUTO KILL SHIT TOO.
Barbarians: This seems cool, thematic, and balanced. (Semi confused as to what "Fury" is...)
Monks: Bad. Really bad. (see below)
Rangers: Interesting game play mechanics, seems to be balanced. Thematic. Yes, it requires a lot of consumables, but, it provides a lot of options.
Lenses of the Owl: Better power for a 3 star transmute. Is the +1 to attack, to damage, both? Needs clarification
Ring of Fevor: Really like it. Interesting combination (melee and spell)
Charm of Timely Aid: I like it. Wonder if it would be better as a 3 star transmute instead.
Ring of Stamina: As others have said, would prefer to see a +3 con ring. Still a good ring, don't know if the power level is a 4 star transmute.
Selfless Savior Stone: Weird. I don't know what the thought process is behind this is. Don't know if I would make this with PoDD or Potion Root Revival floating about.
Monk:
Sigh. This needs help. The comparison between the 1st Monk relic (which was bad) and the current iteration is comical. The 1st had: +4 melee dmg, +2 AC. The current has: +3 melee dmg, 1 additional stun per 3 games, 1 auto kill per 10 games (on average, assuming a consistent slider, which is questionable at best). Auto-kills are not very fun to me, and, looking through the forums, that seems to be the consensus. Not to mention, the 19s and 20s on the combat boards are small. Try, please, to get two 19s or 20s. I'll wait. Tell me how many slides you had to do. Still working on it? Thought so. The likelihood of this EVER coming up is so, so small, it's not worth it. Especially on the class legendary. Maybe a rare monk weapon, that could be interesting. Yeah, I went there. The auto-kill requirement of 2 monk pucks land on a 19 and 20 is a rare level power in my mind.
Possible fixes for the Monk (some of it, I've said before):
Expanded stun range (could limit it to 1/monster/room)
Increase saves (monastery training)
Increase AC (unarmored defense)
summon shadow clones, absorbing an attack, basically giving +1 activation of shadowskin
"Unleash the dragon" AOE attack. Call it out and attack 1 target. melee damage splashes to other enemies.
Self-healing or temporary health mechanic similar to an enhanced version of the healing from Ring of Dark Health.
Disarm mechanic reducing physical damage of enemy.
Something psychic-related like "immune to charm, possession and other character loss-of-control effects".
Messing with Psychic is fine, but make it worthwhile. It's too situational for a legendary.
Avoid instant kills.
References and people I've talked with on this post:
Phil
Randy
https://truedungeon.com/forum?view=topic&defaultmenu=141&catid=55&id=249862&start=108#342979
https://truedungeon.com/forum?view=topic&defaultmenu=141&catid=55&id=249929&start=96#344864