Reading through the Basic Rules for D&D 5th Edition, I am struck by how much more powerful wizards are at low level. Maybe this is just a reaction to my having spent the majority of my reading on B/X D&D and AD&D 2nd Edition, but the important magic missile spell is a good indicator of the relative power level of these games.
In B/X, a magic missile shoots one magical projectile which hits for 1d6+1 points of damage. A first-level magic-user has one 1st-level spell slot, and so the maximum amount of damage they could do in a single encounter without resorting to melee (pro tip: don't) is 7 points.
In AD&D 2nd Edition (and apparently 1st Edition as well), magic missile does 1d4+1 damage. A first-level mage has one spell slot, while a specialist in Evocation would have two; assuming both of these are used for the same spell, the most damage a wizard could do in one encounter is 10 points. A mage would only be able to to half this damage, at maximum.
In D&D 5th Edition, magic missile shoots three missiles for 1d4+1 force damage each! Also, first-level wizards have two spell slots, meaning that they could potentially do up to 30 points of damage in a single encounter - in addition to damage from cantrips like ray of frost! I'm picturing something like the spaz-lasers from The Lords of Magick, rather than the kind of fearful, fragile wizard portrayed in Dragonslayer.
True, the ability to shoot additional missiles was present even in B/X, but there a magic-user had to wait until 3rd level or higher before being able to launch multiple magic missiles!
It sucks having been the DM by default for such a long stretch of time; I find myself wanting to change things (like nerfing this spell, for one thing) as I read through 5th Edition. The reason I don't is that I want to experience this new version of D&D as a player first, and then as a DM. I feel like the new Starter Set will go a long way toward accomplishing this, but I still have to hold my house-rule instincts in check.