Fortune and glory, Kid. Fortune and glory.

I have ranks 3,4,7 and 11 of Healing Touch on my bar, depending on what I am assigned depends on what I do.
I still need some upgrades to allow me to cast rank 4 without losing mana but I can spam rank 3 and gain mana back slowly.
This lets me use my mana pool as an emergency heal pool and still be able to keep healing after the emergency is over.
Rank 3 Healing Touch only gets ~55% of your +healing bonus but unlike the priest heals the cast time is shorter.

I have been playing around with HealPoints which sums things up quite nicely for you in game :)
HT3 puts out about 330 HP/s with my current gear.

I also have max rank Rejuv and Regrowth on my bar, I haven't looked into down ranking these as it doesn't seem to give the same advantages as HT gets.
If you are casting a regrowth it is normally because someone needs a large heal ASAP and as a druid this is it, without using NS.
It you are casting Rejuv it is because you want the tic's to keep someone topped up or to swiftmend away, either way you want the highest rank.

Edit. HT4 heals for about 1000, so like the rest of you this is what I aim for :)

Lower ranks of HoTs is pretty much the most mana efficient spell you can cast. It's pointless in raids where everyone is healing everything because the target will be overhealed anyways. But if you've got a group and it's YOUR responsibility to keep them alive (C'thun/Viscidus are places I use it a lot), it's awesome. If your target is down ~600hp, toss them a rank 1 renew for 58 mana instead of overhealing them and letting your mana go to waste.