The Druid has always been a problematic D&D or AD&D character class, for me. I never understood the point of drawing a distinction between a druid and a cleric; like the barbarian, which is surely just a fighter who happens to be from a certain cultural background, the druid must surely only be a cleric who happens to worship nature, or a nature god, of some kind. The division between the two classes is entirely arbitrary and artificial, and also rather blandly Eurocentric (Christian versus pagan).
The D&D druid also flies in the face of almost everything I know about real druids (which admittedly isn't very much and is mainly gleaned from Julius Caesar's writings). These weren't hippy-dippy nature lovers, by most accounts: they were astronomers and diviners, who also acted as judges in Celtic society and had a penchant for burning people alive in giant wicker structures, a la Edward Woodward.
That said, the druid is also probably my absolute favourite 2nd edition AD&D class, and the one I played the most during my formative years. I put this down to two factors:
2) You get to call yourself a "heirophant".
Over the next few days I'm going to put up my 'take' on the druid as a character class for LOTFP, focusing on these two factors: shapechanging and heirophancy. Watch this space.