That's odd that your tanks are taking more dmg. It feels like ours are taking less, but it may be the difference between 25/10s and having more healers. I'll go over our parses from this week when we go and see if we have a difference too.
LK you'll probably have a bit of trouble still since it's just a long fight. Before we could easily sit and wait for fsr regen to to kick in. I could get to 100% mana between phases, but now it's a lot different.
You're gear is about the same as mine, besides the few bis pieces you're missing as you said. From armory(unbuffed blahblah) as for major stats I only have 300 more sp, unnoticeable less haste and more crit, and 200 more in combat mp5 but not any huge difference besides that. Your spi is a bit lower but still not a huge difference.
You even have furor. With your stats you should easily be able to heal the way you do without any big problem, esp on fights like princes. 3 healing is shitty but if your disc isn't able to keep up or your raids standing in things you may have to go to 3 heals with no fault of your own =/
Check other WoL parses with restos for 10s and see if the dmg taken by everyone in general is drastically different or if your disc is a lot lower than others. Because it really doesn't seem like it's a problem on your end, just you having to heal more then you should in general.