Refreshing path is not supposed to be a cast and sit HoT like templar rune/cleanse or arcanist field, there's a reason it has major expedition. Its supposed to lay a path for the NB to get out of immediate dodge towards some LoS and it gives a small heal along the way to help facilitate that by mitigating some of the DoT pressure that will be ticking while the NB cloaks and runs. I've used it countless times this way and it is crazy good in IC where there is LoS everywhere and good (smart) movement means that the path is not exposing where I am, it gives a general area of where I was, but not where I am unless I am not moving well enough.

For Dark cloak, many have suggested for that morph and offering to be swapped, so NB is forced to choose the assassin or brawler playstyle, not have both at the same time. It is still a class HoT and if this suggestion was at least tested, then yes it would be entirely relevant to the discussion. It is also still a HoT that is native to the NB class kit.

Concealed also gives you minor expedition at all times. With how efficient NB bar space is, it is very easy to slot it just as a buff skill for berserk + expedition (something I have done on my current NB build). Put it this way, NB is giving up far less to slot concealed for its passive buffs of berserk + expidition than sorcerer is giving up to slot camo hunter/inner light exclusively for major prophecy/savagery.

Crit surge as a "HoT" is being carried entirely by the change to wards that allowed them to scale from stacking health. Crit surge also scales from max health. Before this change crit surges heal was barely above siphoning attacks heal, even though it had the much harder to proc condition. Sorcerer also doesn't have an inherent way to reliably proc crit surge anymore, the recent change to melee attack range and the change to the tick rate in U35 took care of that. Siphoning attacks has half the tool tip, but it procs every 0.7 seconds (this is the rough cooldown of light attacks), while crit surge has a built in cooldown of 1 second that hard caps the skill no matter how frequently the sorc crits (which is much harder to achieve than it is to simply light attack.
Siphoning attacks also gives a really nice burst of sustain (on par with dark conversion, the mag morph that gives increased resources) that cannot be prevented/countered. It requires pre-casting it, but this is something that can be done in cloak iirc and can be utilized to great efficiency to get another round of burst or healing (or cloak) in before NB must disengage to recover their resources.

No, I am not saying that NB should be forced to ulti gen to heal (even though NB has some of the best ulti gen in the entire game thanks to the catalyst and transfer passives).

Are you suggesting I use anything but my offensive ult in PvP?

As a solo player you should know how essential defensive ultimates are to surviving in outnumbered fights. There's a reason every non-NB slots and uses an ultimate that is, at the bare minimum partially (if not entirely), defensive on the back bar. By not slotting something that is at least partially defensive on the back bar you are giving up any notion of surviving those intense pressure scenarios (unless of course you're on a NB and cloak covers for that).

That one line you said goes to prove just how absurdly broken cloak is as an ability, it is so strong that it completely replaces the need for an entire defensive ultimate on a class that is supposed to struggle to survive. If that is not overpowered and in desperate need of adjustment, then nothing is and all other classes should have all of their nerfs reverted.