I usually play hybrids also, but it's more of an almost 'pure' with a just a touch of some of the other 'class' skills; most of my characters choose 80-90% of their perks in one 'class'. Also, I find it is better, at least for me, to level up only a few skills at a time - levelling too many causes problems due to abilities being spread too thin. My current character (12th) only has perks in block, heavy armor, one-handed, and smithing (and only one perk here so far). But this is not a 'pure' build because I am also working on alteration (slowly and no perks so far); and I also plan on getting conjuration - eventually. By the time I'm 20th, I'll probably have a perk or two outside the warrior skills, perhaps a handful by the time I'm 30th, and maybe 10 non-warrior perks by 50th.
I am having a blast playing 3 pure characters. A fighting-man, a magic-user, and a thief. Each do totally different quest lines and have different motivations--which ties into the quests. My fighter completed the companions and dragonborn questline, and continues to follow the way of the voice with the monks while joining the bards college,
my wizard does all the dwemer quests after becoming head of the college (him being a seeker of lost knowledge) and raids the outcast conjourers keeps and castles in search of the means to use the atronoch forge. The key to playing a "pure mage" for me is to focus on the wizardly abilities of illusion, conjuration, enchanting, and alteration. I hardly use destruction as that turns the wizard just into another "combat" class. With telekenisis, invisibility, magic item creation and mind control my character feels pretty "magical".
and my minimal combat thief did the monumental task of rebuilding the thieves guild and will take out the dark brotherhood when I get around to it (my thief is a bit of a gray mouser character and the DB is a good stand in for the Lankhmar thieves guild) while becoming as rich as humanly possible.
What's most important I think isn't pure/hybrid, but having a strong character concept--something this skyrimblog does a really good job of fostering. But if you're going to go the Joseph Campbel "universal hero" route of using one character to play the whole game, then I think a hybrid character is probably the right choice.