I really don't get the whole removal of "levels" / addition of "tiers" debate. Isn't it just the same exact measurement of time? SoE already did this whole tier thing with EQ2. Even in the original game (all the bs mechanics aside), 1-10 = T1, 1-20 = T2, 21-30 = T3, 31-40 = T4, and 41-50 = T5. Now think about it for a second because yes, there were still levels but everything else about the tier system were identical. You were geographically locked out of higher tiers, all gear was locked to your appropriate "tier" (or lower), your spells / abilities were all according to your "tier". Each tier progressively just added +gooder stats, ability, and power.
To me, it just seems like the same old tiering locks but instead of levels as the unit of measure, its gear... and lets be honest, it all just meanstime investment.
Same old same old.
You can break anything down to just pressing buttons and getting some kind of feedback. The issue here is you are glancing over all the nuance and design of different attempts. Before WOW came out, you could of just said "aren't you just grinding mobs anyway? Want's the whole point of quests?" Obviously disguising mob grinding with a task oriented system made the game a million times more successful. That's not debatable at all. Obviously it's not the only reason, but it is a core point.
So let's take that a step further. Every single game out there now (with the exception of TSW but they still do it anyway in a different fashion) starts you off at level 1. SWTOR, Rift, EQ1&2, WOW, GW2, TERA, Archeage, Wildstar. They all do it. The game, from a design point of view, is broken into two halves. We all know this, but let's break it down for argument sake.
The first half is a linear quest path that generally consists of collecting tasks and finishing them. Each of the games above does this in different ways. EQ1 has you going from spot to spot in a linear fashion grinding mobs. GW2 has you going through a progression of completing zones and doing hearts. SWTOR and Wildstar have you following a plot line through a zone, completing tasks along the way. However, in each case you have a zone specifically designed for a tight level range, content is gated inside that range by a specific level restriction. Once you finish that level range, you are done with that area forever. The lower the level, the faster it's consumed.
Obviously each game has other activities that you can pepper in to make it less monotonous. Some games you can grind mobs instead where it's more efficient, or dungeons, or battlegrounds. But in the end, the vast majority of players that play the game, follow the designed quest route.
The second half is a game where your level is based on the totality of your gear. The game then becomes you running through various dungeons, instanced or otherwise, with various amounts of people.
A Tiered system breaks down that dichotomy. Everyone here basically rushes through the first half (which consists of 90% of the developed content) in a few days of playing and spends the rest of the time playing the game in the second half. So why create a game that caters to the portion of the game you spend the least amount of time on? Why not create a game where each tier is essentially "the end game". Do you not have the most amount of fun collecting gear and beating big bad guys? Why not make a game solely based on that?
So you take away the grind of leveling up, and just stick everyone in that first tier of end game. Just hope the people designing the game are smart enough and good enough to make sure there is a path to follow in the game that isn't rigid like a linear quest path. Unfortunately I don't think there is enough creative people in the industry to do that. The majority of MMO devs aren't smart enough to create a complicated system, and just default to what they've seen for 15 years. We just need people who can create open world maps and dungeons like Zelda (any of them but 2) or any of the Dark Souls, or any of the GTA maps.
