I almost exclusively play tanks in this game. I've tanked on every class, and currently have 4 classes as tanks (and a templar healer). I used to tank primarily on my nightblade back pre-morrowind when sap tanks were still an option. The massive and, in my opinion, unwarranted change to siphoning strikes has nearly crippled nightblade tanks in all aspects of the game.
Every other class has some means by which to recover stamina outside of the usual constitution/recovery benefits.
Warden: Bull Netch / Nature's gift
Dragonknight: Helping hands / Battleroar
Sorceror: Dark Deal
Templar: Repentance
Nightblades had siphoning strikes, which at one point cost magicka and would return magicka and stamina 10% of the time you used other abilities. The new version of strikes only restores stamina (or magicka, based on morph) on light and heavy attacks, and for tanks costs more than it restores in most situations. You need a net total of 9 hits to restore just the casting cost of the ability - tanks simply do not throw light and heavy attacks out that often, even if they arent permablocking.
Something needs to be done about this to make nightblades a viable tanking option again. If it's true that ZOS wants every class to be capable of filling every role, and wants each class to have a skill tree more or less dedicated to a specific role as they've done with wardens and are slowly doing to the other classes, nightblade resource management needs to change.
Obviously the best option would be a change directly to siphoning strikes, but I doubt ZOS will go back on what they've already screwed up and make additional adjustments. Ideally, siphoning strikes and its morphs should have no resource cost, or should be toggled abilities once more, in order to make their stamina or magicka return viable for characters that arent sitting there spamming nothing but light and heavy attacks. Alternatively, instead of being based on light and heavy attacks change siphoning strikes to return resources on any damage or healing done by the nightblade or his abilities (inc. dark shades). That would allow a tank to cast it and reap the resource return from his shades and damage over time effects rather than having to constantly light or heavy attack..
Other options include some kind of stamina return on a shadow ability (which they seem to want to be the tank focused tree) - possibly dark shades (returns stamina whenever hitting an enemy, magicka for the bow version) or an alteration to aspect of terror/mass hysteria/manifestation of terror, as none of the fear abilities are currently conducive to tanking (or anything outside of pvp, lets be honest here). Another option could be adjustments to one of the shadow cloak morphs - again a useless ability for tanking as it drops aggro (though it wasnt always so) to instead give resistances and stamina return rather than invisibility (but obviously leave one morph for invisibility for those who use it). Maybe change dark cloak to something like "Chameleon: grants minor evasion and minor protection for 10 seconds, but no longer grants invisibility. Dodging, blocking, or being hit by an attack while active restores x% of your max stamina."
I'm open to other ideas, but I'm at a loss as to how to keep my nightblade tank even viable at the moment.
PS4 / NA
M'asad - Khajiit Nightblade - Healer
Pakhet - Khajiit Dragonknight - Tank
Raksha - Khajiit Sorcerer - Stamina DPS
Bastet - Khajiit Templar - Healer
Leonin - Khajiit Warden - Tank