Which faction has more powerful leaders/important lore figures?
As an Alliance player I may be a bit biased but it always seemed to me that the alliance leaders were way more powerful than the horde leaders.
This is my view of the leaders, feel free to add your opinions, that's why I'm posting. I will include leaders who died in Legion because of the lack of development in the expansion.
Horde:
Thrall - Obviously very powerful (provided the elements are present), a solid warrior and the most powerful shaman in the known universe (not counting temporary weakness during Legion). When fully powered by elements he can do insane stuff, even when he was a novice he destroyed Durnholde through the earth element. Downside - VERY dependent on the elements, as seen in Legion, SOO, and a few other occasions.
Vol'Jin - A shadow hunter whose powers are not so clearly shown, but he is thought to be incredibly agile, capable of standard witch doctor stuff like hexing, and is known to be greatly skilled in battle. Trolls also have enhanced regeneration although I don't see that helping in a single battle to death.
Baine Bloodhoof - A warrior for whom we can assume is as strong as his father was, which means he is a capable and a skilled warrior. As a tauren he obviously overwhelms some of the weaker alliance races by default, but that's about it.
Lor'themar Theron - One of the most experienced leaders of the Horde as he fought in the Amani war, the Second and the Third war. He was a ranger second in command only to Sylvannas at one point, which implies he is very skilled with his bow and arrow, even for elven standards.
Jastor Gallywix - Praise be upon him, the most powerful leader of all, he can unleash a torrent of coins onto his enemies until they get squished by the weight.
Sylvannas Windrunner - Very though to rank, because her base abilities are being the best ranger out of all the blood elves, meaning probably in all the Horde. In practice she is way more powerful because she uses all the dirty tricks she can through her subjects to do things that are incredibly useful. But since it's through her subjects, and not her directly, I can only attribute that to her cunning.
Varok Saurfang - Probably the most experienced Horde leader, as he fought in all three wars, and almost all campaigns. Obviously very strong and very skilled.
Notable characters:
Drek'Thar - Very wise and powerful shaman, also a strong warrior.
Hamuul Runetotem - A powerful druid, knows many secrets of the wild.
Lady Liadrin - A relatively new but strong paladin.
Alliance:
Varian Wrynn - To keep it short, a proven warrior, probably one of the most successful human gladiators.
Gelbin Mekkatorque - A brilliant engineer, but we've only seen him in action on the Broken Shore, he seems to be doing pretty well with a huge, gunned robot.
The Council of the Three Hammers - While each of them is fairly strong and have a rich history, none of them stand out as exceptional, at least the way I see it.
Genn Greymane - You guessed it, another cool warrior guy.
Now for the powerful guys I was talking about
Prophet Velen - Velen is probably the most powerful user of the Light and he is incredibly old and wise. For the denizens of Azeroth his power would seem on an otherworldly level (see what I did there?). The downside is that in combat his full power doesn't really show, since his power is more on the defensive side (heals, protection) and visions.
Malfurion Stormrage - The first and the most powerful druid by far, he taught Hamuul Runetotem and all the other druids the ways of druidism. He is basically one with the nature in every sense, and skilled in every school of druidism, which means that in combat he could adapt to every situation, and change the battlefield itself the way he wants.
Tyrande Whisperwind - Through Elune she's probably the second only to Velen when it comes to wielding the light. Unlike Velen though, Tyrande is exceptionally skilled in combat, as seen in many occasions, as she can use both her powers, and her weapons to do some stuff.
Notable characters:
Khadgar - Presumably the most powerful mage on Azeroth (could be wrong though), and technically the new Guardian as claimed by medivh in RtK. Prior to Gul'dan's powerup in ToS, he easily overpowers him, thanks to both his pure power and his experience.
Jaina Proudmoore - Along with Khadgar one of the top mages. She could have crushed the entire city of Orgrimmar with a single spell had she not changed her mind in the last minute.
Shandris Feathermoon, the Windrunner sisters.
My point is, apart from Thrall, the horde leaders are just very skilled warriors/archers, while the Alliance leaders are consisted of a few very skilled warriors/archers, and a few godlike power users. Any thoughts if you cared enough to read this lengthy post?
P.S. Sorry pandas