What specs are your other members using? Depending on party composition, Wynne's 2nd spec could vary. But as expected, shapshifter always stay as a no-no.
Altho you want her to be your primary healer, only two spells that are woth it in the SH tree are the first two. You can modify Wynne into your main healer/ off-CCer to help your melees or archers (and works quite well. You simply need paralyze, glyph of paralyze and blood wound to make this work. Petrify is great as well, mass paralyze works great against group of mobs that do not have blood. Earthquake is questionable, your melees are gonna suffer a bit, great for rangeds tho, and repulsion nets you some amount of CC and in addition to that, nets you even more CC potential with paralyze explosion) Speccing into Blood Mage only for blood wound is really useful and yes, worth it.
And no, going with Arcane Warrior is not bad. Just get combat magic so you can use massive armor. With this and Return to Ostagar DLC, you can build her into a tanky healer with calians armor set (requires Return to Ostagar DLC).
But i would go with blood mage. Heck, Blood Wound is way too great. Turn Blood Magic on before battle, blood wound, turn BM off, start swap to other characters and let the AI do the job.
I could do better if you said your party composition, and mainly at which part of the game you are and what is the purpose of every party member.
*edit*
With AH, you can also have a great amount of mana regenration with the following setting:
- It is possible to completely offset Shimmering Shield's -10 penalty to Combat Mana Regeneration if you choose the correct equipment and skills. Combine any of Wade's Superior Dragon Armor Sets (+2 regen) and Andruil's Blessing (+2 regen) with Cailan's Arms (+5.75 regen) and the second tier Combat Training(+0.5 regen). The aforementioned numbers are from the PC version, on Xbox and PS3, you have more equipment options, as the regen amounts are twice as high (except the +5 set bonus from Cailan's Arms).
Taken from http://dragonage.wik...immering_Shield
This is a setup to offset the Shimmering Shield mana drain, but as you will not be using it, instead, you will have a great mana regeneration