There really isn't that much wrong with PvP in Avalon (or wasn't in my day). All of Narissa's points are completely valid and I agree with those which I've experienced personally. However, I don't think any of them are really a 'show-stopper'.
Avalon PvP is crazy hard-core, and if you want you can theory-craft why. Characters in all RPG system (with levels, skills, equipment etc) have a 'Meta Level' which basically a weighted sum of all the elements which factor into the 'power' of every character. You can break the Meta Level down into very small units, but to keep this simple I'll group everything into only three (Level, Items and Player Skill). Let's compare WoW and Avalon and see why I'm more likely to play WoW.
World of Warcraft:
Character Level (including skills)= 60%
Equipment (assuming character level is equal) = 20%
Player Skill (assuming above are equal) = 20%
Ok, like all good statistics I've made them up on the spot. But I think we can all agree that character level (and it's implications on equipment you can use) has the most significant impact on your characters 'power' in WoW. Followed by Equipment and Player skill. NOTE: These numbers are based on PVE in WoW rather than PVP, but I suspect they are not too different (maybe player skill is a little higher %).
Now, Avalon:
Character Level (which is really just skills in Avalon) = 20%
Equipment (potions, magic items etc) = 10%
Player Skill = 70%
NOTES:
Importance of character Level varies from class to class, and I'm also assuming you have the core basic skills: fullparry, fullignore, breakfree etc.
Equipment is VITAL in Avalon, but it is also accessible to everyone very easily (yes I am including basic herbs and poisons) - all it takes is a little time to be completely equipped at ANY level. So, theoretically this is higher than 10%, but I am assuming that we've all covered the basics like potions and magic items.
So, what can you draw from these numbers.
Firstly, getting your character 'powerful' in Avalon tests the player differently than WoW does. A powerful WoW character primarily weighted towards character level, then equipment, then finally player skill. Taking each of those in turn: character levelling in WoW generally an easy and safe experience (depending on your server type), you invest a little time and you get a predictable reward out it. Likewise, getting equipment is fairly easy and gives you a fairly predictable benefit for the effort you put in. As for player skill, in PvP it is a lot harder, the skills you gain from levelling up are not that relevant so you have to invest a lot of time and energy without being sure that you'll get any better. It's actually hard. But thankfully (apart from at the HARDCORE PvP level) player skill doesn't count for that much and you can always, easily, go an stop on someone who doesn't have good gear or doesn't have a high level character.
Avalon on the other-hand is different. Give me character with 520 health, 1 Ult to spend as I like, 10k in gold, a friendly lore-master and a dishonest ranger and I'd kill 90% of the currently active players. To compare with WoW that's like saying 'Give me a level 20 character with all green items and 100 gold to spend at the AH and I'd be able to fight in Level 80 Arena' - which is a joke.
So what? Well... this is the fundamental reason why PvP in Avalon both less and more appealing than in other games.
APPEALING: It is more appealing if you happen to be 19 years old, a student, at university, studying a course which doesn't interest you, where it is OK to spend 70-100 hours a week playing a game. It is OK if you can mentally, emotionally and physically invest around 50 hours a week, for 6 months doing little else other than practice combat with no assurance that you'll 'succeed' at the end.
LESS APPEALING: It is not appealing if you are not the above person (or some version of them).
The short version of this post is "Oh, I don't have time to play any more."
The slightly longer version of this post is "Oh, I don't have time to play as much as I would need to if I was to be as good as I would want to be, in order to feel a sense of achievement".
And to answer your question "Demosthenes..." "...What would it take for you to return?" I would say if I lost both my job and my fiancée at the same time, I'd be back in a heartbeat.