From what I see, it's the opposite: he's killing quest givers after completing their missions because that's they're good for. Why does he feel that way? It's the lack of commitment towards these NPCs, which means they're just as valuable as the stuff they have.
Speaking about puzzling with information, it's also a major component of having a smooth / flowing gaming experience for me. Let me present a great example for that, which is the third mission of the Fighter's Guild at Balmora ("Telvanni Agents").
While the first two are totally manageable for even a semi-decent level 1 character, this is much more hardcoe for sure. The Steward told my character that he need to kill 4 individuals who are responsible for certain crimes at the Caldera ebony mines. They're hiding in the cave North to mines, and most likely one of them is on lookout somewhere outside. When I asked her about more informations about the actual persons, it turned out that: one is a kicked out Fighters Guild member, another two are local Dunmer (one is a random nobody, while the other is well-known throughout Azura's Coast) and all we know about the last is that he's a Bosmer. The only thing they have in common is that all of them members of the Thieves Guild.
These are the pure facts that being told to the Player, but what do they mean for us?
- 4 versus 1: being this heavily outnumbered, I won't stand a chance at all unless I'm facing with them 1-on-1
- which is unlikely: caves tend to be lot smaller than mines, both the risk of being detected and facing multiple enemies is higher (e.g. they notice that I engaged in a fight with their fellow and come to his aid)
- since it'd be logical to assign the Bosmer on lookout (as they're typically great Marksmans), he's likely the only one who I don't have to fight in a closed, relatively narrow area
- as for interiors, we have one who is a decent (as the Steward said: "she's stupid but she can fight") Warrior from an unidentified race (based on Thieves Guild practice it could be: Dunmer / Bosmer / Nord).
- two other Dunmers with unknown class, but judging from their membership they should belong to Thief / Rogue / etc. class, meaning: they fast and agile, equipped with light armour and short blade, potentially some ranged weapon
- presumably they're not that well-equipped nor too high level, the rank should look like the following: the "famous" Dunmer > former Fighters Guild girl > noname Dunmer
Now, what could be the solution?
- first and foremost, I need something to help to divide my attacker(s) attention; serve as a bait further opponents; and act as an obstacle if I have to back-pedal
- as I'm playing a (not pure, but still) Warrior, the char's magical ability and mana pool is very limited, so no Spells nor actually usable Enchants for me
- thus I have to rely on Scrolls, and as I need a strong Melee companion the most effective yet available option(s) would be an Atronach(s)
- as at least half 2/3 of my enemies are Dunmers, Fire would be a waste because the 75% Resistance, so it must be Frost or Storm - my vote went to the former thanks to the better price / value ratio
- updating my equipment (full set Steel Armour over Common Clothes / Steel Saber / Steel Tower Shield) should be a must: let's shop cheap Enchanted stuff at Mage's Guild / Temple + get Wayn's Dwemer Jinksword
- still, the game changer would be every Redguard's own Adrenaline Rush power, which puts +50pt on every important skill I'm going to need in fight: priceless!
- aside from to the various Potions I already possess, the ultimate preparation for worst case situations are Almsivi / Divine Intervention scrolls
So that's it. As soon as I took into account all these above (it took only a minute or two), I went to check every what magic users have to offer in Balmora - needless to say I didn't find the scrolls I needed, so after I decided to pay a visit at Vivec. Think about it, where should I find these if not at the biggest city of the continent? Luckily, I was able to get everything during my shopping spree (and spending most of my Gold, LOL). Thankfully to these precautions and the proper plan, I was able to overcome an otherwise surely fatal issue without major losses at level 2.
See, I think these kind of solutions is what Morrowind is all about.