For specifics, burning is only very strong when applied in high stacks. The classes that benefited the most from the burning change were classes that already had strong options, namely the Guardian and Elementalist.
While there is an argument that the burning change was done to make conditions viable in PvE, this only effected classes that already had good PvE options. The guardian was already the centerpiece of every high tier group with aegis and the highest reflect uptime of any class. The Elementalist was already the top tier class in pve.
All of the other classes with the exception of the sinister trapper ranger (while decent, still gets outdamaged by just about every metazerk build), have very limited access to high burn stacks. As a result, they really have not changed in effectiveness due to burning changes. Some actually became worse due to the power gap between burn stackers and non-stackers (Dhuumfire necro, for example).
In PvP the effect was even worse, with classes that had already strong options growing insanely strong with access to high burn stacks.
There are also only a few skills that create serious problems with burning. For the guardian it is mainly passive burning procs that come from Virtue > JI burns > Permeating Wrath, which allows a symbol, whirling wrath, or instant-hit purge conditions to hit a balled group and wipe them in seconds with over 10+ stacks to the group. I would not consider torch skills OP due to how slow the projectile is and how hard it is to effectively land.
For the ele, its ring of fire, which gave the strongest build in the game (D/D ele) the strongest fire application skill in the game. I recall a strawman red post that game out stating “well don’t move in and out of the circle.” Which is fairly weak logic when you consider that one of the game modes requires you to stand in a little white circle the same size as the RoF against a class with multiple cc’s (including a launch) very high area damage, and mobility. Changes to RoF basically gave ele 1vteam dominion over capture points in a single area control skill and can restrict the mobility options of an entire team down to nothing (don’t touch the edge of the circle or die, oh he used burning speed, now you die if you touch the line intersecting the circle too.).
When you consider the above, the problems that make burning overpowered are really few. There are a single skill chain from the guardian end and ONE ele skill. The obvious solution to balancing burning is to limit the amount of effective stacks that a class can push out individually to a much lower level. Skills that deal high burning stacks must be hard to land.
Guardian burn chains and RoF are only broken because they have a high burning uptime reward for almost zero effort. Guardian chains are all passive procs, RoF controls a whole zone with one button. Both are fire and forget and wipe whole teams.
This means that only certain aspects of the guardian chain and RoF need to be nerfed. The only other high burning applicant comes from the engineer with incendiary ammo and blow torch, which follows with the guardian offhand torch of being hard to hit with. I would consider this fine.
As many people have already deducted, burning on its own is fine, it is only a handful of ease of use skills that reward extremely high burns that are OP. Some classes even needs tweaks to burning to make them more effective (e.g. Dhuumfire necro can use a buff, also no one complained about the Berzerker burn warrior elite spec during the open beta weekend).
Most of these problems can be solved with a simple numbers tweak or limit on the burns these current skills can apply. These changes would do little to impact PvE as well. Ele will still be top tier and people don’t bring guardians into speed runs for burns.
(edited by lordhelmos.7623)