I suspect there may be a lot of people who play this way (it's how my friends and I play as well), and this is why I keep trying to advocate (though I think it gets lost in the roar of the RAIDRAIDRAID crowd, heh) for keeping plenty of content at all levels completable with this playstyle. Have enough quests for these groups to level up without having to repeat stuff, and have those quests completable without rare gear or piles of consumables, and you'll keep the casuals. Dissatisfaction with build (at least on the part of casuals) comes more from struggling through quests at level on Normal, and running out of quests before leveling, than any feeling of inadequacy next to the powergamers.