I was pretty much talking of when you've already got runic echo (runic is usually enough to deal massive damage by itself early on and it's better than some lane items for it's price), but while what you say is right, her q is indeed quite easy to dodge when you see it coming, you don't see her q coming all the times, especially in the jungle, where there are a lot of blind spots (if you invade you will probably have a ward there, so you can see the enemy jungler) so it's quite easy to hit at a good enough range. Also she's not a siege mage, but rather an ap assassin, so you can't really compare her with lux, you would need a diana/lb/ekko.
Anyway: nida already has incredible clears, is incredibly mobile in the jungle and has insane burst (more than most junglers) and good sustain in the jungle so giving her even more mobility is not really a great idea (we all have league of mobility creeps, right?), also, you seem to be thinking I would completely take the reset away from her but I wouldn't, what I am saying is: it's fine if she has a reset on kills, but it's a bit overkill if all she has to do is hit you with a skill and can get up to 3 resets in one fight (traps, spear and kill), and that's what they are going to do, you still have a reset on kills, but not on hunted targets, it' just more fair: assassins should all be based around kill resets, if they fail to kill you, they gotta die themselves, that's the only healthy kind of assassin, not "jump in, take 60% hp, jump out, wait 4 sec, jump in, kill, still full hp: GG OUTPLAYED GET REKT N00BZ" which seems to be how people think assassins should be, that's not balanced, not healthy nor fair..
Also: whoever tells you you can't jungle with other keystone is just lying. I've jungled with Thunderlord, Fervor and Grasp (also with bond of stone) and I can assure you strenght of the ages is not a necessity, if you want to invade or gank a lot, other keystone are far better (i've played thunderlord, grasp and bond of stone on sejuani, she takes SO MUCH damage since her first clear is so slow and she has no natural sustain so I can assure you anyone can do it, I managed to take the same 5 camps I could take with strenght of the ages with health per level masteries instead of armor, I was just a bit lower on health, but needed to back anyway). Try other keystones, you might find yourself to recall a bit sooner (I don't think so since nida has decent sustain, she shouldn't really need to recall too much, I personally am not good enough to play her so I didn't try her yet, but if sejuani can do it, pretty much anyone can do it), but strenght of the ages is far from a "must pick", it helps only in the first clear, before the first back, and even then it will just be a slight help, it won't make the difference between having to recall at the 5th or 6th camp. At least I never managade to take one more camp because I had strenght of the ages instead of say Grasp (again, talking about sejuani who has 0 sustain and is slow af in her first clear).
On another note: you will hardly find an opponent full hp and with good mr early game both in lane and in the jungle (unless you talk about top lane), and nida is incredibly similiar to lee sin: her better playstile would be to invade or gank and get the first kills so she snowballs and starts putting all the enemy team behind with constant ganks and invades, and since you can literally invade at level 2 (taking q + w) you can easily find an enemy jungler with half hp at his 2nd/3rd camp (nida has some of the, if not THE, fastest clearings of all the junglers so after buff you can invade and take the kill easily, obviously ward beforehand and be sure you actually can invade), which is enough to get first blood on him and make you snowball like crazy. Now you might argue about nida going against champs like shyvana/udyr/lee who can easily fight her if she tries to invade, but those kinda champions are great duelists early on and have enough damage to fight you and possibily kill you (not at level 2 usually) and are champs designed around searching the opponent and making his life miserable by killing him over and over and stealing ALL of his jungle, and then there are lee and elise, who are exactly like nida: they have strong invades and ganks with decent clears so if you fight them, you play on an "even ground" where they are stronger than you early (lee's and elise's damage is just more consistent than nida's especially early on).
Oh btw, I hope it' doesn't seem like an attack, I want to actually have a conversation on this to better my game knowledge too if I'm mistaken.