The sync change was in 5.1 actually, the new content just uses the same formula. Basically if you're synced, it's a 100% learn assuming it's not overworld/carnival. It's really nice compared to the shitfest they did in the ARR version.
1000needles was obsolete basically instantly for trash, besides maybe the lvl 15-20 dungeons. It did 1000 spread between targets, 5targets and you're doing 200each, which most other aoes would do also without having a horrible cast time.
Having a ton of fun with BLU parties tbh, the new skills make them really interesting.
I'd say BLU healing is currently more fun than any of the other healer. It has absolute garbage healing tools, Esuna is pbae and terrible range so you can't really dispel ppl without clicking on them to see where they are then running up to them and dispelling tanks is a gamble wether or not you'll just eat a cleave, aoe heal is either the same terrible range or White Wind which is OP but really mana hungry, you have no instant heals at all, your rez is on a 5mins cooldown so better hope you're not with a bunch of retards, but it's still more fun because all the time you're not healing, you have a ton of shit to do, including a shitton of oGCDs to weave. Also when needed they can spam heal the tank better than any healer, cause Pom Cure only costs 200mp but heals as much as the "strong" heals for normal healers which cost 1000.
Tanking is also fun but the damage penalty is way too high so it feels kinda bad, you do just garbage dmg while tanking. Also feels squishy, your only real good defensive cooldown is still Diamondback(you get Thrill but it's just not that great and BLU in general feels squishier). The provoke is also designed like garbage, making it aoe only means picking up a single mob off another tank is a pain in the ass. It's very easy to play though and on dungeons you can remove the tank stance after freezing trash to dump good damage.
And DPS overall is a lot more fun and interesting now that there's more than just one offensive skill. Bunch of cooldowns, bunch of oGCDs, still your dot, it's still kinda spammy but doesn't feel stale like it used to. It's not Ninja complexity but it's pretty fun.