One thing that I liked and hated all at once from 4e was minions. In D&D Next I find myself ioccasionally wanting them back again.
What I liked about 4e minions: Their ability to be strong in their attack and to hit a PC of a particular level.
What I disliked about them: The 1 hit point of health seemed a little silly and enables PCs to exploit some AoE attacks.
Problems with D&D Next solution: So far, it seems like the solution to the minions idea in Next, is to use creatures as they exist. The design seems to attempt to make it possible for low level monsters to be able to hit upper level PCs. While I like this concept, these creatures, with their +2 to attack, have little hope of actually hitting higher level characters that are running around with a 20+ Armor Class. Consequently, they see these creatures, such as a zombie horde, as a joke, and don't fear even a hundred of them.
We are currently running Legacy of the Crystal Shard at level 5 and the PCs are in the Dwarven Mines and are about to fight zombie hordes. I am trying to structure the fight so that there are large numbers of zombies that they have to deal with. They are not really that strong in that they have few hit points, however, if they get up in your business, they should be able to land an attack on you, even if the damage isn't lethal. If enough of them are on you, the damage will eventually take you down so shear numbers are a factor. I can't do this with the Zombie as it exists right now. They would hardly ever be able to hit the melee classes with High ACs, even when surrounding them with advantage, etc...
What I think I'm going to do:
I am thinking of altering the stats of the Zombie, so that they have an appropriate chance to hit the PCs. I will not alter the damage or their Hit Dice, but I think they need to fear being surrounded and overrun by the creatures. Leaving their current HD makes them fairly vulnerable in that if a character lands an attack blow, it will one shot a zombie most of the time.
How have others handled the need to large numbers of minions type creatures?