Enough With the Immunity and more

I remember when DnD Next was first being discussed, long before the playtest materials were anywhere close to being released and the design goals were being discussed. One of the topic points was that players and monsters could too easily gain immunity to damage/elemental types and/or status effects which limited options for both DM's and PC's. I let the Monk slide when it first came out and am now regretting it. Too many classes gain Immunity to several status effects, reducing types of encounters DMs can build.

Barbarian: Frightened (while raging), works with me
Druid:  Poison, Disease, Charm or Frightened (from Fey or Elementals)
Monk: Poison, Disease, Charm, Frightened plus Advantage on all Saving Throws against spells
Paladin: Frightened and creatures within 10ft have advantage, Disease
Ranger: Frightened (Dragon Slayer) 

Of the 9 classes available, 4 are automatically immune to being frightened and another has a good chance at being immune. This goes against what WotC prommised they would strive for. The called for bonuses and resistences, not flat immunities not not prevent diversity of play. The advantage and disadvantage system was supposed to replace random numerical bonuses, why can't it replace flat immunities? In some instances, I can settle for immunity. Raging Barbarian or mindless undead? Fine with me. But as for the Monk having 4 immunities, perfect stats at 20, and advantage on all saving throws is unacceptable (51% minimum sucess chance.) Replacing most immunities with advantage increases the chance to negate the effects without flat out preventing tactics for the DM or PCs, something that as someone who is a Player and DM, would greatly appreciate.

Also, in the last Beastiary, 24% of monsters had Magical Resistance, meaning Widards (and now Druids) that rely on their spells to deal damage cannot use their AoEs having to rely on single target spells. All Demons, Devils, and Dragons share this trait. This forces spellcasters to rely on their higher level spells to increase the damage on a sucessful save, or use single target spells, which in a larger battle reduces their efficiency and forces them to use more of their daily spells. I do not know what one can really do about this but I think it should be something looked into as, by my count, there are 6 non-cantrip Wizard spells that do not use saves to deal damage, one of which is Magic Missile. Since their spell damage is already balanced based on spell level and against martial PCs that attack AC, a quarter of the Beastiary punishes spellcasters.  Not in the Read First file, almost all spell attack rolls have been replaced with saves and Magical Resistence has been removed from most creatures that had it in the previous packet.

Furthermore, Wizards are devoid of an attack bonus while Druids, who share the same number of spells per day gain a +2 bonus.
I think you mistake is in assuming that the DDN designers have "promised" anything.

Usually what they say is more along the lines of "we would like to" or "we think that" or "our current idea is". 



Also, Casting in Armor (How to Play 22) says "you must be proficient with the armor you are wearing to cast a spell." 
Doesn't change the fact that they are moving back towards invalidating abilites used by players and the DM. If you can reasonably expect half the party to be flat out immune to the Frightened condition, why even bother making creatures that ues it? The effect can hit half the party while the other half doesn't even bother to roll, making some players feel like they picked the wrong options. I also enjoy halloween games that make heavy use of fear effects in both 3.5 and 4e, as well as espionage games that involve poison use, both are hampered by flat immuniteis. BBEG enters the fray, armies tremble, the level 1 paladin shrugs his shoulders. Advantage helps PCs surpass normally challenging saves from foes aboth their level and hardly notice the effects of those at or below their level. A level 1 PC should not be immune to spells cast by Asmodeus.
Doesn't change the fact that they are moving back towards invalidating abilites used by players and the DM. If you can reasonably expect half the party to be flat out immune to the Frightened condition, why even bother making creatures that ues it? The effect can hit half the party while the other half doesn't even bother to roll, making some players feel like they picked the wrong options. I also enjoy halloween games that make heavy use of fear effects in both 3.5 and 4e, as well as espionage games that involve poison use, both are hampered by flat immuniteis. BBEG enters the fray, armies tremble, the level 1 paladin shrugs his shoulders. Advantage helps PCs surpass normally challenging saves from foes aboth their level and hardly notice the effects of those at or below their level. A level 1 PC should not be immune to spells cast by Asmodeus.

I agree, except for the last sentence. Why shouldn't he be? If a character has an ability that says he is flat-out immune to fear, why should the source of the fear-causing effect matter?

Isn't the ability to stand firm while the dragon bears down on you and the rest of your army flees in terror part of what makes the characters heroes?
The problem is that I agree and disagree with you at the same time to an extent. Yes, the players should be heroic, they should not be infaliable though. There are examples in literature and other sources, in which a normally stoic individuals meet something that pushes them past their normal threshold. Immunity prevents events like that, which can add to the story, from occuring. The DM should never overrule a charactersheet written RAW in my opinion, even for plot/story/character development. A PC with immunity to being frightened can never have the experience of fleeing from a foe in fear due to a bad save only to face them again a few levels down to road and overcome them. Mechanically, there is no way for that kind of story element to occur. Resolve can be shaken and fears can triumph in storytelling; and through events like these characters can develop and their players can enrich their experiences.

Also, jumping back to the issue Magic Resistence found in 25% of the beastiary, I retract my previous statement about spell-casters having around 6 spells that target AC, that number has gone to mostly none, aparently the new packet has moved towards saves except for 2 new spells Shillelagh and Flame Blade, which I'm disapointed to see as Druid only. Furthemore, they fixed the number of creatures with Magic Resistence from a cursory glance as fewer Demons (only the level 2 Quasit) and more powerful Devils share this trait, though Dragons still possess it and golems dropped from immunity to magic to resistence. Thank you dev team. 
heh... Infallible and fearless are not the same thing. In fact, often they're quite the opposite. Standing your ground while the dragon bears down on you and the rest of your army flees in terror is stupid. It might work, but it's stupid. 

And frankly, I don't think any player should ever be subject to the unfortunate experience of being compelled play his character in an arbitrary manner for any length of time simply by the whims of the dice. It is one of the most singularly un-fun roleplaying experiences possible, in my experience. Any characteristic of an RPG that can be acurately described as "random and arbitrary" is bad design, or at least lazy design.

To my mind, if the characters are fleeing in terror from something, it should be because the players are legitimitely afraid for their characters' lives. 
I have a feeling the two of us are fixed at our personal prefrences, even if I were to take your position on that specific example, I would feel as if too many immunities were handed out at too early of levels. 5 classes can gain immunities, most, if not all, for each class are granted them, before level 10, Monk being the possible exception.
Well, allow me to clarify: I agree with you. I think the prevalence of blanket status effect immunities is lazy design that ultimately does the game more harm than good.

However, I also believe that uncounterable "gotcha" effects (like being compelled to flee for x time because of a failed roll) are bad design that should be gotten rid of entirely. 

My point about the characters fleeing because their players are afraid for them wasn't meant to be because the characters are immune to some effect that compels them to flee. It was meant to be because effects that compel them to flee don't exist in the first place.

We're on the same page on this one; I'm just doing a poor job of explaining myself, I think.