On a one-minute single-boss fight, 1 % of spell crit buys the same healing as 11.0 healing power, and 1 % of casting speed the same as 37.4. Point for point, MP5 is worth 0.02, Spirit 0.01 and Intellect 0.21. Each figure comes from moving a single stat up and down on the benchmark gear, so it prices the next few points you add from here.
Per point
- Healing power1.00
- Intellect0.22
- Mana per 5 s0.02
- Spirit0.01
Per 1 %
- Casting speed37.4
- Spell crit11.0
Healing power
Every other weight is quoted in points of healing power. One point gives rank 11 Healing Touch 100 % of itself and rank 4 85.7 %, a Rejuvenation 100 % spread over five ticks, and a Regrowth 92.5 % across its direct heal and nine ticks. Each party member gets 33.5 % from a Tranquility channel and 23.1 % from a Wild Growth. Your healing talents multiply the result.
Crit
Crits heal for 150 %. The 16.0 % on your sheet includes 4 % from 
Nature's Majesty and 3 % from the party's Moonkin Aura. Only the heals you cast can crit in our model: Healing Touch, Regrowth's first heal and Swiftmend. Ticks never do, although the 24 September notes let Rejuvenation, Wild Growth and Tranquility crit.
On a single target that is still most of the healing, and on two and three minutes a percent of crit buys about three times what a percent of casting speed does.
Spirit, MP5 and Intellect
Spirit returns 15 mana every 2 seconds plus 1 for each 5 Spirit, and 
Reflection keeps half of it coming while you cast. 
Living Spirit, Blessing of Kings and the Mystic Mushroom idol turn each point of gear Spirit into about a third more. Inside Innervate it pays five times over, all of it mid-cast. MP5 pays in full every second, casting or not. Intellect gives 15 mana a point, plus 10 % from Blessing of Kings and 10 % from 
Heart of the Wild, and 1 % crit per 60.
On three minutes MP5 comes first at 1.74, then Spirit at 1.20 and Intellect at 1.00, none below a point of healing power. A two-minute fight leans more on the size of the bar, and Intellect climbs to 1.64.
A one-minute single target barely values mana stats at all: the bar is never emptied, so a bigger one heals nothing extra. Intellect is worth 0.21 there.
Casting speed
Faster casting speeds up Healing Touch, Regrowth and the global cooldown. On two and three minutes mana stops you before time does, and 1 % is worth just 2.06 on three minutes. On one minute it shows 37.4, the biggest weight, but that number is a step rather than a slope. The casts fill the minute almost exactly, so slower casting drops the final Healing Touch, and that loss is most of the measured weight. The Skyborne's 1 % barely shows on that fight's race board.
Pre-raid gear rarely carries it. The Minor Haste glove enchant and the Skyborne racial's 1 % are your sources.
On every fight
Match your gear to your usual fight length. For two and three minutes, take Spirit, MP5 and Intellect next to healing power, since on these sets each is worth at least as much per point. For one minute, take healing power and crit.