I redid my Resto Druid UI to lower the memory usage. This uses very few addons and little memory. Grid is the highest at around 2.6 MB, the next two are both in the 600-700 KB range. It is also fairly clean and gives a large viewing area.
Focus and target frames are not shown in this picture, since I hadn't set my focus yet and I wasn't targetting anything.
Addons:
Bartender4 - 1-6, R, T, Y, F, G, H keybinds on 4 bars, selectable with Shift 1-4.
Deadly Boss Mods
Fatality - reconfigured lua to announce in its own channel.
Grid
GridAutoFrameSize
GridManaBars
GridStatusHots - corner indicators for my hots, also currently showing shields for LK encounter.
GridStatusMissingBuffs
GridStatusRaidDebuff - showing Infest in the screenshot.
oRA3 - showing raid cooldowns.
pError - removes red error text when I spam keys.
Quartz - for GCD spark and casting bar (not shown)
SexyCooldown
SunnArt - adds black space at the bottom and resizes viewing area.
TidyPlates
TidyPlates_ThreatPlates
TipTac - removes tooltip clutter from the screen during combat.
Please feel free to PM me with any questions or suggestions.