Now, as for how I think that healing could be made easier:
1. We need a better interface. The default interface is horrid for healing and even worse than horrid for information gathering. Give us a way to click on a party member and see with that click all the buffs and debuffs on him. That would be very helpful to us new healers, and perhaps to all new players.
You can already see all buffs and debuffs on any player. Just click them (Or their name in the health bar window, or hit the appropriate F key) to put them in your focus orb. Then hit the magnifying glass in the orb, or hit U to examine them. The list of buffs and debuffs appears, though you won't get any information on their item effects (such as immunity to poison from a belt, or +5 str from their gloves)
2. Numbers over the hp bar. Make it a turn-on-able option for each person to see numbers for all party members. That way, if you want to see it you can, and if not, you don't have to, just like you can for yourself. A bar is cute, but useless for learning how effective certain spells are, or deciding which one is best at that time.
Most people learn pretty fast which spells are worth using on whom. Rogues, casters, and dex rangers need low power spells, barbarians will barely feel even your best spell (until Heal that is). WF always need your most effective spell.
3. As for players, use common sense. Don't run through the trap the rogue is disabling, don't wake up the casters the bard has locked down with fascinate, don't try to beat down level 8 elite skellies with two swords when you are level 3
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And stay in line of sight! I can't heal you if you are three rooms away.
As some clerics have said before, you can't heal stupid hehe.
As for donations, I take them if offered, but have never asked. Overall, I like DDO healing, it's fun and most players are good team players and I have yet to have felt as if players were taking me for granted. In my case, it's been the opposite, in fact.