As a healer main the first time I stepped into the new 55 FPs I did notice some interesting mechanics compared to the previous FPs, e.g. need to cleanse, healers pull more aggro etc...
The main trick is as with all FPs is to know the boss fights, most of the bosses that have hard hitting dots, i.e. last boss on Athiss don't hit that hard normally so your job as a healer is just to keep an eye on the dots. With 2.0 this is easier as you can resize the debuffs but if you dont want to do this just keep an eye on the whack-a-mole bars and when you see a party member taking ~3k/sec then cleanse. All healers should have their cleanse skills hotkeyed (i.e. mine is hotkeyed as Z)
I actually like the added challenge in the new 55s and once you get 2-3 pieces of Black Market the FPs are very easy, hell a well co-ordinated team should be able to run through these FPs. It helps if the tank and healer has confidence in each others abilities and that the DPS follow the trash rotations, i.e. weakest->strong, tank should be strong->weak. Only exceptions to this rotation is to pull aggro off the healer, which we get more of now.
In each new 55 FP there is always a challenging area to heal through, Mando Raiders I am looking at you with the dog pulls, but with a little strategy the pulls become relatively trivial.
The new 55 FPs (like the unnerfed LI HM) teach people to use all their skills, i.e. tanks need to taunt and position correctly, dps need to know when to drop aggro and focus fire (also a CC/interrupt occasionally would be nice
) and healers need to be able to cleanse, manage their energy and keep up the tank. This in turn allows players to progress into Operations which should be the goal of the Flashpoints, ie. teach the players the mechanics as this was skipped mainly through levelling