mp5 is far superior to mana in my experience. I roll with 16 mp5 while casting but <1600 mana in arena. I very rarely oom. I usually value 1mp5=2.4int, the only place where i would not pick up mp5 is with rings of concentration and the cape of the elder, the trade off is too poor.
Your shoulders should be preened ironfeather, but if you dont have them on your server for whatever reason then the ones you have are perfectly fine. I would also recommend using Dignified Headmasters Charge instead of the mace for your 22int weapon, the staff has more stats and for a healer int > stam on a starter weapon. I do have a 22int mace for 5v5 arena sets and PuG FCing though.
As the others said you need to change your cloak. Battle Healer is just poor, Spidersilk or Tumultuous Cloak of the Sorcerer are both superior. If you are going for hit rating, in arena its nice, not so usful i find as a defensive healer in WSG, use spidersilk, otherwise use sorcerer. Also i would strongly advise changing your cloak enchant, 15 nature resistance is very useful against shamans who will melt your face with purge and windshear if you're not careful.
I would drop one AGM for insignia, being hibernated/feared/sapped etc will put your team at a lot of risk if you are unable to heal for 8 seconds or so, much more useful than an extra 12 stamina. In most situations i run with just over 1k-1.1k hp and it is enough in most situations. On a similar note i use Aquarius Belt in arena and situations where i get a lot of unwanted attention, the extra cooldown is very useful and with the amount of mp5 and stam you have you wont really miss the stats. Also the hit rating is nice for arena and the crit is semi useful in arena too.
If you can pick up Seal of Wrynn, but if you cant dont worry too much sylvanas is fine.
Your spec is alittle dubious too. Personally i love moonglow, its one of my favorite talents availible to druids, however you have to give up subtlety for it which is just far too useful for the spec to be viable. Also genesis is crap. No point taking it, it will add about 3.5 healing to each tick of your hots at most. If you are going to go balance i would recommend putting your first 5 filler points in Starlight Wrath, not terribly useful for a defensive healer in WSG, but in arena and duels it is very useful, it will significantly increase your dmg output, and wrath is dirt cheap and does enough dmg to make it worth while to throw out a few wraths. 8/0/2 is my favorite Druid spec, however the most functional resto spec imo is 0/0/10, 3natures focus, 2 imp motw, 3 subtlety, 2 natural shapeshifter. This will increase your resistance to dispellers significantly and imp motw and natural shapeshifter will give you some mana efficiency to make up for not having moonglow. This is better than 8/0/2 from a resto PoV because resistance to purgers is vital and difficult to pick up, whereas mana can be found in many places.
Glyph of Rejuv is good, for a minor glyph MOTW is the only contender, thorns doesnt cut the mustard and dash is worthless.
I know this seems like a massive wall of text, but your druid is essentially good
I hope you have fun with it.
