Again a few thoughts.
I want to show my POV about the leveling rates:
Imho 3x rates are the best compromise for both sides. The type of players who like to enjoy every bit of the questing and instance zones. With 3x rates they won't need to skip to much quests before hitting 60 and doing instances before will give them enough reward to leave them satisfied and not to think about them as a waste of time considering xp/hr is it is on most highrate servers. Low instances are sadly dead on most 4x+ rate servers.
On the other hand you got the type of player who wants to be 60 asap. They won't be forced to change the questing zones after a bare handful of quest in each zone, what was definitely the most painful part of leveling in classic wow after release and still was at 1.12. Doing 3-5 quest on one end at the word and trevel 20 mins to do the same amount was really anoying.
When the leveling rates are to low you will distract a certain amount of players. Even when this server is way better then every other around they won't invest to much time in leveling again.
Another point I want to adress is the impact of old characters.
Afaik they should return after a few weeks when Nefarian is killed for the first time.
This is way to early! I will show you a scenario to explain why:
Depending on luck the most competitive raids will got ONE full t2 tank at this time, when old charakters are unlocked at this moment they will get access to more then just one full t2 tank what makes raiding much more comfortable. And raids who don't have killed Nefarian at this time will get an even larger boost on their equipment. This is no gamebreaker at all, but will lead to an unattractive situation.
To weaken the whole situation you got only few options. One could be to to unlock the old characters after the C'Thun kill. Then a good amount of the competitive raids has set their foot into AQ40, the t2 content is still strong but the invading amount of characters won't generate such a huge advantage as it would be after the Nefarian kill. Another would be to hardreset the server at all, and never unlock the characters.
In addition to this i would strongly recommend to never unlock bank alts, especially guildbanks.
The amount of high value materials like arcanite bars, elementium ore, lava/fiery core will harm the whole economy for at least one/two months. Not to talk about possible dupes (something that always can happen, and not savely observed)..
All in all i would recommend to send out an email with an poll to ask the community and old players if they want their old characters back. This don't has to happen in a hurry, better let the poll open for at least two till four weeks, to get enough feedback to be sure, not to displease your own community.
At last something not so harsh. The beautiful showcases!
At the moment the showcases are our best advertising. So i want to add a few thoughts about possible future issues.
The Scepter of the Shifting Sands questline!!!!
This is the most amazing questline ever happend in whole wow, i got the honor to host the questline with my guild on Ysera EU. And most people done the questline will sign this, and even the once who just know about it think they missed something really great!
A whole showcase at some time will adress alot of players who missed the questline and may even retail players who want to enjoy it. But enough of all the hype for the questline. The great question is how to represent the whole event?! Best way would be to test everything with enough people on the testserver and show the event from this (test-)server! No old footage, just own material! This would be really awesome and i guess it would impress alot of people! But it would be alot extra work for the whole team. But it would also secure a smooth event then the server would be live... Okay i guess its still something we can talk about in the future.
Another thing that comes to my mind are the instances! They got so much attention by the DEVs so it would be a waste to not show the workling events or even the scripted details like the npc spawns in AB from the last showcase. So why not show something awesome scripted from every instance started by RFC. In every showcase you can show 2-4 instance depending on the amount of unique things.
I'm almost sorry for everyone who read this whole text
But if you did, please share your opinion.