Current state of the Thane?

Yes, great idea. Let's implement one of the worst changes ever seen on live to shoehorn an already strong class into a consistent role in 8v8 play. Group versus group play is largely a question of optimization-- this is why proper hybrids will rarely find consistent success in the format outside of gimmicky roles. When a Thane is casting on a target you'd really rather have a proper caster in its place, and when a Thane is meleeing a target you'd really rather have a proper melee in its place. Phoenix attempted to address this by essentially increasing both aspects of the Thane's skillset to be a little more powerful, and I think the changes were pretty successful overall. You aren't losing quite as much when taking a Thane instead of a more specialized class, plus they have ST. The downside is you are still losing out comparatively in almost any situation the Thane finds itself in, and the flexibility isn't as valuable in a meta game revolving around efficiency and specialization.

Live's designers understood this issue too, and realized that in order to give certain hybrids a role in a game type that revolves around specialization you had to make hybrids specialized. The solution was to massively buff hybrid melee DPS across the board, and to lazily award a number of classes a leviathan-type style without any consideration of class identity and balance in other styles of play. Thanes and Valkyries received massively buffed style lines with anytime DDs and leviathan. Valewalkers received the GR/conflag chain as well as a change that made BB a two style chain. Not only did these changes have the undesirable effect of homogenizing builds for the classes they affected (sword was clearly the superior weapon line, and 50 scythe was not optional), but they served to massively increase the DPS of the classes affected. So now we had hybrids that were essentially specialized in terms of being melee DPS, and they would be used in competitive groups on the assist train. Or at least that was the idea (they still didn't have stoicism...)

The problem is no consideration was given to how badly this wrecked the balance in other parts of the game. See, there is a fundamental problem with leviathan-type mechanics-- there is essentially no counter play if you do not have purge available or the type of reliable spam healing you'd find in an 8v8. If a Reaver slams you and you don't purge you have almost no chance of turning the fight around if they get a full series of levis off. The fight is over before it began and you are relying on a 10-15m CD to counter a combination that they can use any time. Now, imagine giving this capability to classes that don't have a fairly weak spell line and relatively low stats across the board. It becomes even more problematic. All of a sudden the solo and small man landscape is purely made up of the classes that have access to these proc styles because they were already fairly viable, and now they have access to massive situational DPS that cannot be avoided without purge. The visible meta game becomes purely focused around being able to counter these overpowered classes in some way if not playing them outright. This is much like what we are seeing currently on Phoenix with much of the visible meta being primarily focused around dealing with assassins in some way.

The reality is some classes will simply never be viable in 8v8 gameplay. Not only is this completely OK, but it is to be expected. The goal with design decisions should never be to force optimization for the sake of the 8v8 game mode, but it should be to buff weak classes while retaining their identity. It is fine that Thanes aren't the best in groups but are great at solo/small man/zerging. They received appropriate buffs and now seem to be in a great spot relative to other classes without becoming levi bots.