Hi,
I originally soloed as a druid healer and grid works pretty good and monitored HoTs pretty good. Currently as a boxer I am using Vuhdo which seems to monitor HoTs pretty well in solo mode (i.e. when am on the druid and watching his UI when healing out of combat). The big win with a druid is that they can get back mana from spells which bloom and so makes them really great on long fights.